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A Resource Guide for Philosophy Students

Created by Jennifer Leslie Torgerson, MA

This page last modified:  October 15, 2012

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School of Athens



384 – 322 BCE



Aristotle, The Politics; Ernest Barker, Editor and Translator.  (London, UK:  Oxford University Press, 1958 [1946]).

__________, Metaphysics; Richard Hope, Translator, (New York, NY:  Columbia University Press, 1960 [1935]).

__________, On The Soul; Hippocrates G. Apostle, Translator.  (Grinnell, Iowa:  The Peripatetic Press, 1981). 

__________, The Metaphysics:  Books Zeta, Eta, Theta, Iota (VII-X); Montgomery Furth, Translator.  (Indianapolis,  IN:  Hackett Publishing Company, 1986 [1985]).

__________, The Metaphysics; John H. McMahon, Translator.  (Amherst, NY:  Prometheus Books, 1991). 

__________, Nicomachean Ethics; David Ross, Translator.  (London, UK:  Oxford University Press, 1991 [1925]). 

Jonathan Barnes, Editor; The Complete Works of Aristotle: The Revised Oxford Translation, Two Volumes.  (Princeton, NJ:  Princeton University Press, 1995 [1984]). 

__________, The Cambridge Companion to Aristotle.  (Cambridge, UK:  Cambridge University Press, 1996 [1995]).

Frederick Copleston, S.J., A History of Philosophy:  Book One.  (New York, NY:  Doubleday, 1985 [1944]). 

Walter Kaufmann, Philosophical Classics Volume I:  Thales to Ockham, 2nd Edition.  (Englewood Cliffs, NJ:  Prentice Hall, 1968 [1961]). The majority of the primary source quotes were taken from this text.



The works of Aristotle



De Interpretations


Prior Analytics


Posterior Analytics




Sophistical Refutations




On the Heavens


On Generation and Corruption




On the Universe


On the Soul


Sense and Sensibilia


On Memory


On Sleep


On Dreams

On Divination in Sleep


On Length and Shortness of Life


On Youth, Old Age, Life and Death, and Respiration


On Breath


History of Animals


Parts of Animals


Movement of Animals


Progression of Animals


Generation of Animals


On Colors


On Things Heard




On Plants


On Marvelous Things Heard






On Individual Lines


The Situations and Names of Winds


On Melissus, Xenophanes, and Gorgias




Nichomachean Ethics


Magna Moralia


Eudemian Ethics


On Virtue and Vices








Rhetoric to Alexander




Constitution of Athens





"All men by nature desire to know." Metaphysics 980 a [1].


Aristotle's Metaphysical Realism:


Aristotle rejected the Form world of Plato, and the third man argument is, too, Aristotle's criticism of this position. Plato was the first to discuss this problem in his dialogue called "Parmenides."

Consider the relationship of a thing to its form. Should not the form be in the thing itself- is it not this form and matter which makes the thing what it is? Aristotle says:

"[a]bove all one might discuss the question what on earth the Forms contribute to sensible things, either those that are eternal or to those that come into being and cease to be. For they cause neither movement or change in them."

Metaphysics (991 a [9-10]).


How does the Form relate to the thing in the sensible world if they are in two different planes? How does this Formal knowledge get to the sensible world? How, indeed. The form and matter are what make a thing the thing that it is and Aristotle felt that this was the proper metaphysic. Forms must be in things. This is a type of realism (the theory that universals such as Forms, must exist only within the objects in the external world, as opposed to the realm of Ideas or Forms).

Therefore how on earth can Plato be a realist if he held the latter view that Forms of things exist only in the Formal realm?  (Some do consider realism to merely mean that there are universals or forms for things, and in this narrow sense, Plato can be called a realist).

Plato was an objective idealist. It is this objective idealistic position which Aristotle wishes to refute with his realistic description of the world. Some call Aristotle's view is a type of metaphysical naturalism because the logical empirical nature of his method, and the forms are found in nature. But most naturalisms also reject a supernatural source, or cause of the universe, and this is in contradiction to Aristotle's religious position, which will be explained shortly, of the Prime Mover, which is Pure Act (because the Prime Mover is not seen, its being is inferred from the fact that things which move now need to be moved by another, and this cannot go on to infinity, hence there must be a first, unmoved mover, which is the source of movement in all other things).  

But it must be noted that even the Prime Mover is a substance. Any definition of anything necessarily involves a reference to substance, because the knowledge of substance is logically prior to the consequent knowledge of other categories such as size, quantity and shape. First, the substance must be known prior to any knowledge of particular things. Aristotle's view is actually a type of naturalism because of the empirical nature of the position, for how else is substance known but accept from the apprehension of these substances, in nature, by the five senses?

(Note Ockham's Razor, briefly, to illustrate the other problem of the One over the Many: that Plato has multiplied entities, such as the creation of the realm of Being, without necessity. The realm of Being is not necessary to the existence of an objective reality. "Entities are not to be multiplied without necessity.")

The so-called correlation between the Form of Man (3rd Man), man 1, and man 2 is not adequate. What actually makes the correlation happen? Plato never really tells us, he uses metaphor and allegory to try and dispel this logical difficulty. If there is a relation between the 3rd man, man 1 and man 2, then is there not the need for an explanation as to what they all have in common as well? This is known as the fourth man. This 4th man also needs to be related to the 3rd man, man 1, and man 2, and hence a 5th man is required to explain to explain their similarity and a 6th and so on, ad infinitum (to infinity). This occurs because there was never an adequate explanation of why the 3rd man or the Form of man imparted its essence or form upon the things in the world. A logical leap was made and the demonstration of the regression makes this logical leap apparent.

The argument of the 3rd man also illustrates further the main difference between Plato and Aristotle: the location of the forms of things. Plato argues that forms are in a transcendental realm, separate from things they impart their essence upon; but Aristotle felt that the form must logically be in and of the thing itself- or immanent (inherent; the form is indwelling in the matter). The problem of this separation (or chorismos in Greek) Plato postulated between the material and its form was logically contradictory according to Aristotle. (The problem of the chorismos). The same root is in the word chromosome. Think of the helix and its two separate sides.

Aristotle had a view of hylomorphic composition (coming from the Greek words hyle = matter, and morphe = form) which is the view that the natural world has a twofold composition, namely that of matter and form. Aristotle did not use this phrase himself but he did discuss his theory of the four causes in his Metaphysics (1013a -1013b).

" 'Cause' means (1) that from which, as immanent material, a thing comes into being, e.g. the bronze is the cause of the statue and the silver of the saucer, and so are the classes which include these. [this is the material cause]. (2) The form or pattern, i.e. the definition of the essence, and the classes which include these (e.g.: the ratio 2:1 and number in general are the causes of the octave), and the parts included in the definition. [the formal cause]. (3) That from which the change or resting from change first begins, e.g. the adviser is the cause of the action, and the father of the child, and in general the maker of a cause of the thing made and the change-producing of the changing. [the efficient cause]. (4) The end, i.e. that for which a thing is; e.g. health is the cause of walking. For "Why does one walk?" we say; "that one may be healthy"; and in speaking thus we think we have given the cause [the final cause]."


Examples of the 4 causes

material cause


formal cause


efficient cause

melt bronze, pour in mold

final cause

bronze statue of Athena

Aristotle's theory of the Prime Mover:

1069 b [27] "Nonbeing has three senses. If, then, one form of 'nonbeing' exists potentially, still it is not by virtue of a potentiality for any and every thing, but different things come from different things; not is it satisfactory to say 'all things are together'; for they differ in their matter, since otherwise why did an infinity of things come to be, and not one thing? For 'reason' is one, so that if matter also were one, that must come to be in actuality which the matter was in potency (an undifferentiated unity). The causes and the principles, then are three, two being the pair of contraries of which one is definition and form and the other is privation, and the third being the matter."

Some key words as defined by Aristotle

-( Metaphysics 1018 a- 1022 b [25]):

potency: means the source of movement or change, which is in another thing than the thing moved. (also potentiality- in contrast to actuality- the domain of actual facts, or the achievement of a things' full potential.)

privation: if something has not one of the attributes which a thing might naturally have, even if this thing itself would not naturally have it; e.g. a plant is said to be 'deprived' of eyes.

1071 b [5] "Since there were three kinds of substance, two of them physical and the one unmovable, regarding the latter we must assert that it is necessary that there should be an eternal unmovable substance.  For substances are the first of existing things, and if they are all destructible, all things are destructible. But it is impossible that movement should either have come into being or cease to be (for it must always existed), or that time should. For there could not be a before and an after time if time did not exist. Movement is also continuous, then, in the sense in which time is; for time is either the same thing as movement or an attribute of movement. And there [1071 b 10] is no continuous movement accept movement in place, and of this only that which is circular is continuous."

1069 a [30]

physical substance


immovable substance





There must be a higher reason for why substances exist.

(essential substance [ousia]:  the this; whatness; what a thing is; what it was to be)

"But if there is something which is capable of moving things or acting on them, but is not actually doing so; there will not necessarily be movement; for that which has a potency need not exercise it. Nothing, then, is gained even if we suppose eternal substances, as the believers of the Forms do, unless there is to be in them some principle which can cause change; nay this is not even enough, nor is another substance besides the forms enough; for if it is not to act, there will be no movement. Further, even if it acts, this will not be enough, if its essence is potency; for there will not be eternal movement, since that in potentially may possibly not be. There must then be such a principle [1071 b 20], whose very essence is actuality. Further, then, these substances must be without matter; for they must be eternal, if anything is eternal. Therefore, they must be in actuality.  Yet there is a difficulty; for it is thought that everything that acts is able to act, but not everything that is able to act acts, so that potency is prior to actuality. But if this is so, nothing that is need be; for it is possible for all things to be capable of existing but not yet to exist." [...]

Prime Mover is Pure Actuality

1072 a [9] "If, then, there is a constant cycle, something must always remain, acting in the same way. [10] And if there is to be generation and destruction, there must be something else which is always acting in different ways." [...]

Prime Mover as the unmoved mover and uncaused cause because it hasn't any material or potentiality.

1072 a [15] "[T]here is something which moves without being moved, being eternal, substance, and actuality. And the object of desire and the object of thought are the same. For the apparent good is the object of appetite, and the real good is the object of rational wish." [...]

1072 b "That a final cause may exist among unchangeable entities is shown by the distinction of its meanings. For the final cause is (a) some being for whose good an action is done, and (b) something at which the action aims; and of these the latter exists among unchangeable entities though the former does not. The final cause, then, produces motion as being loved, but all other things move by being moved. Now if something is moved, it is capable of being otherwise than what it is." [...]

Prime Mover as Simple First Cause

"But since there is something which moves while itself unmoved, existing actually, this can be in no way otherwise than as it is." [...] 1072 b [10] "The first mover, then, exists by necessity; and in so far as it exists by necessity, its mode of being is good, and it is in this sense a first principle." [...]

Prime Mover as Thought Thinking Itself

"On such a principle, then, depends the heavens and the world of nature.  And it is a life such as the best we enjoy, and enjoy but for a short time (for it is ever in this state, which we cannot be), since its actuality is also pleasure.  (And for this reason are waking, perception, thinking most pleasant, and hopes and memories are so on account of these.)  And thinking in itself deal with that which is best in itself, and that which is thinking in the fullest sense with that which is best in the fullest sense.  And thought thinks itself because it shares the nature of the object of thought; for it becomes an object of thought in coming into contact with and thinking its objects, so that thought and the object of thought are the same.  For what which is capable of thought, i.e. the essence, is thought.  [...]  And life also belongs to God; for the actuality of thought is life, and God is that actuality; and God's self-dependent actuality is life most good, so that life and duration continuous and eternal belong to God; for this is God." Metaphysics 1072 b [15-30].

Problems with the Prime Mover as Thought Thinking Itself

"The nature of the divine thought involves certain problems; for while thought is held to be the most divine of things observed by us, the question how it must be situated in order to have that character involves difficulties.  For if is thinks of nothing, what is there here of dignity?  It is just like one who sleeps. And if it thinks, but this depends on something else, then (since that which is substance is not the act of thinking, but a potency) it cannot be the best substance; for it is through thinking that its value belongs to it.  Further, whether its substance is the faculty of thought or act of thinking, what does it think of?  Either of itself or of something else; and if it is of something else, either the same thing always or of something different.  Does it matter, then, or not, whether it thinks of the good or of any chance thing?  Are there not some things about which it is incredible that it should think?  Evidently, then, it thinks of what which is most divine and precious, and it does not change; for change would be change for the worse, and this would be already a movement.  First if it thought of the act of potency, it would be reasonable to suppose that the continuity of thinking, is wearisome to it.  Secondly, there would evidently be something else more precious that thought, viz. that which is thought of.  For both thinking and the act of thought will belong even to one who thinks the worst thing in the world, so that if this ought to be avoided (and it ought, for there are even some things which it is better not to see than to see), the act of thinking cannot be the best of things.  Therefore it must be of itself that the divine thought thinks (since it is the most excellent of things), and its thinking is a thinking on thinking."  Metaphysics 1074 b [15-35]

Primary substance and Secondary substance

(from the Metaphysics)

"[W]hat is sought long after both long ago and now, and always, and always puzzled over:  what is being? -- is just [the question], what is substance?  (for this some say is one, others more than one, and of the latter, some say it is limited, and others unlimited);  for which reason it is for us too to investigate ["theorize"] most of all, and primarily, even -- so to speak -- exclusively, concerning that which is in this way [= substance], what it [primary being] is." Metaphysics 1028 b [2-7].

"Being or that which is is said in many ways, as we went through earlier in our remarks 'on the number of ways' [in which things are said] {at Delta 7}; for it signifies, on one hand, the 'what it is' and 'some this', and on the other hand, so 'so-qualified' or the 'so-much' or each of the other things-predicated as there are.  But through what is is said in so many ways as this, it's evident that primary among these is the 'what it is', for it's that which signifies substance (for when we're saying how-qualified this thing is, we say [it's] good, or bad, but not three-cubits, or man;  but when [we're] saying what it is, [we say] not pale, or hot, or three-cubits, but man, or god); but the others are called beings by the way of being, some, quantities of what is in this sense, other, qualities, other again, afflictions, still others something else." Metaphysics 1028 a [10-20].

Aristotle had in fact, many different uses of the term substance.

"Substance is said, if not in more ways, at least chiefly in four:  that is, [1] the essence and [2] the universal and [3] the genus seem to be the substance of each thing, and fourthly, the subject of these." Metaphysics  1028 b [33].

Primary substance is what cannot be said about a subject.  It is best referred to as the this (as if you were pointing).

Secondary substance is that which can be said about a subject; about which we can make descriptive statements.

"A substance -- that which is called a substance most strictly, primarily, and most of all-- is that which is neither said of a subject nor in a subject, e.g. the individual man or the individual horse.  The species in which the things primarily called substances are, are called secondary substances, are also the genera of these species. For example the individual man belongs in a species, man, and animal is a genus of the species; so these-- both man and animal-- are called secondary substances. [...] It is reasonable that, after the primary substances, their species and genera should be the only other things called (secondary) substances.  For only they, of things predicated, reveal the primary substance.  [...]  Further, it is because the primary substances are subjects for everything else that they are called substances most strictly." Categories 2 a [11]- 2 b (29). 

Categories 1 b [25]


(what cannot be said about a subject)


(what can be said about a subject)


substance (man or horse)


quantity (4 feet)


quality (pale, literate)


relationship (half, larger, greater)


place (Lyceum)


time (yesterday)


posture (sitting)


state (has shoes on)


doing something (cutting)


undergoing something (being cut)

In these uses, throughout the discussions of Plato and Aristotle essence is equal to form, or that which makes a thing what it is.

Aristotle's empiricism:

Empiricism is the view that all knowledge is derived from sense experience, or a posteriori, which is Latin for "that which follows after". Therefore empiricism is the belief in knowledge which follows after sense experience. Literally it means "experience-ism" since empeiria meant experience in classical Greek. As discussed earlier in the course, empiricism is to be contrasted with rationalism. Plato was a rationalist and Aristotle was an empiricist. Aristotle held that the mind was a blank tablet (clean slate) or tabula rasa. The tablet is only filled with knowledge after sense experience. This is in contrast, again to Plato's rationalistic position of recollection of prior knowledge.

 nous: Greek for mind and according to Aristotle it was the intellect, which he distinguished between the active (eternal and immortal) and the passive.

Aristotle had a view that universal ideas were existent in the mind, but yet necessarily derived from sense experience.

Things are particulars and their qualities are universals. So a universal is the property predicated of all the individuals of a certain sort or class. For example, redness is a universal, predicated of all red objects. Universals have been claimed by some philosophers to have an existence distinct from the particular things instantiating the property. Plato, for example believed that the observed world is only a reflection of the real world, which are the Forms, which are something like universals. For the idealists, only universals have "real" existence, and particular objects become mere collections (or mere representations) of universals.

But other philosophers, such as Aristotle claimed that universals have "mental existence." It is by comparison of an object with the appropriate universal that we are able to attribute the appropriate property to the object. Thus we are able to say that a car is red by comparing the color of the car to our mental conception of redness. This is discovered through induction as Aristotle tells us: "Thus it is clear that we must get to know the primary premises by induction; for the method by which even sense-perception implants the universal is inductive." Posterior Analytics [100 b]. But Aristotle also said: "Sense perception is common to all and therefore easy and no mark of wisdom." Metaphysics, 982 a [11-12].

It is also important to note how Aristotle influenced St. Thomas Aquinas, a Dominican monk born near Aquino, Italy. (c. 1225-1274). St. Thomas called Aristotle "the philosopher" because of his reverence for him. St. Thomas said that "Nothing is in the intellect which was not first in the senses." or Nihil in intellectu quod prius non fuerit in sensu in Latin. Summa Theologica (part I, question 86, article 1). But St. Thomas called this a type of abstraction, because universals are abstracted from the particulars.

The Three Levels of Knowledge According to Aristotle:

[Metaphysics 980b-982a]

(1) mere experience: knows that a certain medicine had done good to X when s/he was ill, but without knowing the reason.

(2) art: the man of art knows the reason, s/he knows the universal, which the medicine will cure fever and X suffers from fever.

(3) wisdom: But Art aims at a production of a certain kind. Wisdom does not aim at producing anything, but at apprehending first principles of Reality. (i.e. knowledge for its own sake).

Aristotle's view of the soul

From De Anima (On the Soul)

principle definition or formula for the soul

"Now one genus of things we call "substance", but (1)  one kind under this we regard as matter, which is taken by itself is not a this, (2) another as shape and form , in virtue of which something is directly called "a this", (3) and third, the composite of the above two kinds.  Matter exists in potentiality; form exists as actuality, but in two senses:  e.g., (a) as knowledge, and (b) as the exercise of knowledge.

Bodies are thought to be substances most of all, especially natural bodies for the latter are the principles of all the rest.  Of natural bodies, some possess life but others do not; and by "life" we mean self-nourishment and growth and deterioration of that body.  So every natural body which partakes of life would be a substance of the composite kind.  And since there exists such a kind of body (for it has life), the soul would not be a body; for a body is not something which belongs to a subject but rather exists a subject or as matter.  Accordingly, the soul must be a substance as the form of a natural body potential with life, and [such] substance is an actuality.  So the soul is the actuality of such a body.

But actuality is spoken of in two ways, as in the case of knowledge and in the case of the exercise of knowledge.  Evidently, the soul is an actuality as in the case of knowledge; for sleeping and being awake depend on the existence of soul, and being awake is analogous to the exercise of knowledge whereas sleeping is analogous to having [knowledge] but not exercising it.  Now in the same individual the knowledge of a thing is prior in generation to the exercise of that knowledge.  In this view of this, the soul is first actuality of a natural body with the potentiality of having life; and a body of this kind would be one which has organs.  The parts of plants, too, are organs, but they are entirely simple; e.g., the leaf shelters the rind and the rind shelters the fruit, and the roots are analogous to the mouth, for both of these take in food.  If then, there is something common to be said about every [kind of] soul, this would be:  "the first actuality of a natural body which has organs".  And in view of this, one should not inquire whether the soul and the body are one or not, for although the terms "one" and "being" have many senses, the dominant sense is that of actuality." 412 a [3] - 412 b [5].

Capacities of the soul according to Aristotle

Rational element (reason or intellect)

Animal element (will, desire, locomotion)

Nutritive element (food, growth, vegetative)

The soul as cause (in 3 senses)

"The soul is the cause and the principle of a living body.  Now the terms "cause" and "principle" have many senses, and similarly, the soul is a cause in the three specified senses of "cause"; for it is a cause as a source of motion, and as a final cause, and as the substance of an animate body.  

Clearly, it is a cause as the substance [of an animate body]; for the cause of the existence of each thing is the substance of that thing, existence in living things is life, and the cause and principle [in living things] is the soul. Further, the formula of that which exists potentially in its actuality.

It is evident that the soul is a cause as final cause also.  For just as the intellect acts for the sake of something, so does nature, and nature's end is a final cause. Such [end] in animals is the soul and [is an end] according to their nature; for all natural bodies are instruments of the soul, and, as in the case of animals, so is in the case of plants, [natural bodies] exist for the sake of their soul.  And, [as already stated] "that for the sake of which has two senses:  (a) that which is done, and (b) that for which it is done.

Finally, the soul is also the cause as a source of motion with respect to place, but such power does not exist in all living things.  Alteration and growth, too, exist [in living things] by virtue of their soul; for sensation is thought to be a species of alteration, and nothing without soul can have sensations.  Similar remarks apply to growth and deterioration; for nothing can by its nature grow or deteriorate without taking in food, and nothing can be nourished unless it shares in life." 415 b [10-25]

equivocation and univocation

"Things are said to be named "equivocally" when, through they have a common name, and the definition corresponding with the name differs for each.  Thus, a real man and a figure in a picture can both lay claims to the name "animal"; yet these are equivocally so named, for, though they have a common name, corresponding with the name differs for each.  For should any one define in what sense is an animal, his definition in the one case will be appropriate to that case only." [...]

"On the other hand, things said to be named "univocally" which have both the name and the definition answering to the name in common.  A man and an ox are both "animal," and these are univocally so named, inasmuch, as not only the name, but also the definition, is the same in both cases:  for if a man should state in what sense each is an animal, the statement in the one case would be identical with that in the other."   Categories 1 a [1-10].

equivocation (equivocal) is also called homonymous.

univocation (univocal) is also called synonymous.


(1)  "Of the species themselves, except in the case of such as are genera, no one is more truly substance than another." 2 b [25].

(2)  "It is the mark of [secondary] substances and of differentiae that, in all propositions of which they form the predicate, they are predicated univocally. For all such propositions have for their subject either the individual or the species.  It is true that, inasmuch as primary substance is not predicable of anything, it can never form the predicate of any proposition.  But of secondary substance, the species is predicated of the individual, the genus both of the species and of the individual." 3 a [35].

(3)  "Another mark of substance is that it has no contrary.  What could be the contrary of any primary substance, such as the individual man or animal?  It has none.  Nor can the species or the genus have a contrary."  {this is too true of the category of quantity}  3 b [25].

(4)  "Substance, again, does not appear to admit of variation of degree.  I do not mean by this that one substance cannot be more or less truly substance than another, for is has already been stated that this is the case; but that no single substance admits varying degrees within itself." 3 b [35].

(5)  The most distinctive mark of substance appears to be that, while remaining numerically one and the same, it is capable of admitting contrary qualities.  From among things other than substance, we should find ourselves unable to bring forward any which possessed this mark.  Thus one and the same color cannot be white and black.  Nor can the same and one action be good and bad:  this law holds well with everything that is not substance.  But one and the self-same substance, while retaining its identity, is yet capable of admitting contrary qualities.  The same individual person is at one time white, and another black, at one time warm, at another cold, at one time good, at another bad.  This capacity is found nowhere else, though it might be maintained that a statement or opinion was an exception to the rule.  The statement, it is agreed, can both be true and false.  For if the statement "he is sitting" is true, yet, when the person in question has risen, the same statement will be false." 4 a [10-25]


Aristotle's Virtue Ethics

Eudaimonia: the activity of a being where happiness (in accordance with virtue) is the end. (eudaimonia is happiness in ancient Greek). 1177 a 15.

Happiness is only achieved in the rational life (animals and plants cannot be happy).  1098 a 1

Happiness is an activity of the soul.  1100 a 1

"But we must add 'in a complete life'.  For one swallow does not make a summer, nor does one day, and too one day, or short a time, does not make a man blessed and happy."  1098 a 16

There is a distinction to be made between an activity (such as building a house) and the state (of being a house).  1152 b 10.

“Every art (techne) or applied science (episteme) and systematic investigation, and similarly every action and choice, seem to aim at some good; therefore the good has been defined as that which all things aim.” 1094 a [1-4].

“The highest good (...) must be something final. Thus, if there is only one final end, this will be the good we are seeking.” 1097 a [28-29]

Happiness is final (an end) and self-sufficient (an end in itself).  When you have happiness, you do not want anything else.  Pleasure is not an end (but a means) and it is not final or lasting. Pleasure is limited and not enduring.  Pleasure cannot be the highest good, but all pleasures are not bad, such as the pleasure from contemplation.  Hence, given the right person, and the right circumstance, some pleasures can be goods, when chosen by those worthy (with qualification).

"The study of pleasure and pain belongs to the province of the political philosopher; for he is the architect of the end, with a view to which we call one thing bad and another thing good without qualification.  Further, it is one of our necessary tasks to consider them; for not only did we lay it down, that moral virtue and vice are concerned with pains and pleasures, but most people say that happiness involves pleasure; this is why the blessed man is called by a name derived from a word meaning enjoyment [makarios].

Now (1) some people think that no pleasure is a good, either in itself or incidentally, since the good and pleasure are not the same;  (2)  other think that some pleasures are good but that most are bad.  (3)  Again there is a third view, that even if all pleasures are good, yet the best thing in the world cannot be pleasure.  (1)  The reasons given for the view that pleasure is not a good at all are (a)  that every pleasure is a perceptible process to a natural state, and that no process is of the same kind as its end, e.g. no process of building of the same kind as a house.  (b)  A temperate man avoids pleasures.  (c)  A man of practical wisdom pursues what is free from pain, not what is pleasant.  (d)  The pleasures are a hindrance to thought, and the more so the more one delights in them, e.g. sexual pleasure; for no one could think of anything while absorbed in this.  (e)  There is no art of pleasure;  but every good is the product of some art.  (f)  Children and the brutes pursue pleasures. (2)  The reasons for the view that not all pleasures are good are that (a)  there are pleasures that are actually base and objects of reproach, and (b)  there are harmful pleasures; for some pleasant things are unhealthy.  (3)  The reason for the view that the best thing in the world is not pleasure is that pleasure is not an end but a process.

These are pretty much the things that are said.  That it does not follow from these grounds that pleasure is not a good, or even the chief good, is plain form the following considerations.  (A)  (a)  First, since that which is good may be so in either of two senses (one thing good simply and another good for a particular person), natural constitutions and states of being, and therefore also the corresponding movements and processes, will be correspondingly divisible.  Of those which are thought to be bad some will be bad if taken without qualification but not bad for a particular person, but worthy of his choice, and some will not be worthy of choice even for a particular person, but only at a particular time and for a short period, though not without qualification; while others are not even pleasures, but seem to be so, viz. all those which involve pain and whose end is curative, e.g. the process that go on in sick persons.

(b)  Further, on kind of good being activity and another being state, the processes that restore us to our natural state, are only incidentally pleasant; for that matter the activity at work in the appetites for them is the activity at work in the appetites for them is the activity of so much of our state and nature as has remained unimpaired; for there are actually pleasures that involve no pain or appetite (e.g. those of contemplation)[...]"  1152 b -1153 a

The 3 kinds of lives:

(1) enjoyment

(2)  political

(3)  contemplative

The life of contemplation is the best and most happy life.

(also see 1177 a 15 - 1179 a 1 or page 230 in your text).

"To judge from the lives the men lead, most men, and men of the most vulgar type, seem (not without some ground) to identify the good or happiness with pleasure; which is the reason they love the life of (1) enjoyment.  For there are, we may say, three prominent types of life-- that just mentioned, (2)  the political, and thirdly the contemplative life.  [...]  A consideration of the prominent types of lives shows that people of superior refinement and of active disposition identify happiness with honour; for this is, roughly speaking, the end of political life.  But it seems too superficial to be what we are looking for, since it is thought to depend on those who bestow honor rather than on him who receives it, but the good we divine to be something of one's own and not easily taken from one.  Further, men seem to pursue honor in order that they may be assured of their merit; at least it is by men of practical wisdom what they seek to be honored, and among those who know them, and on the ground of their virtue; clearly, then, according to them, at any rate, virtue is better.  And perhaps one might even suppose this to be, rather than honor, the end of political life.  But even this appears somewhat incomplete;  for possession of virtue seems actually compatible with being asleep, or with lifelong inactivity, and further, with the greatest sufferings and misfortunes; | [...] The life of money-making is one undertaken under compulsion, and wealth is evidently not the good we are seeking;  for it is merely useful and for the sake of something else.  And so one might rather take the aforenamed objects to be ends, for they are loved for themselves. But it is evident that not even these are ends; yet many arguments have been wasted on the support of them.  Let us leave this subject then."  1095 b 8 -1096 a 13. 

Two kinds of justice defined

distributive justice:

Person A + thing C to person B + thing D.

The problem of distributive justice is to divide the distributable honor or reward into parts which are to one another as are the merits of the persons who are to participate.  

If A (first person) : B (second person) : : C (first position) : D (second position),

then (by alternando) A : C : : B : D

and therefore (componendo) A + C : B + D : : A : B

In other words the position established answers to the relative merits of the parties.

Aristotle explains:  "As the term A, then, is to B, so will C be to D, and therefore, alternando, as A is to C, B will be to D.  Therefore the whole is in the same ratio to the whole; and this coupling the distribution affects, and, if the terms are so combined, effects justly.  The conjunction, then, of the term A with C and of B with D is what is just in distribution, and this species of the just is intermediate, and the just is proportional.  (Mathematicians call this kind of proportion geometrical; for it is in geometrical proportion that it follows that the whole is to the whole as either part is to the corresponding part.)  1131 b 12-14

rectificatory justice

In the case of distributive justice the consideration was of man to man or an equal state of affairs, while sometimes there are situations where one is treated unjustly by another and this is a kind of inequality. Judges are used to equalize such inequalities. Aristotle explains:

"This is why, when people dispute, they take refuge in a judge; and to go to the judge is to go to justice; for the nature of the judge is to be a sort of animate justice; and they seek the judge as an intermediate, and in some states they call judges mediators, on the assumption that if they get what is intermediate, they will get what is just.  The just, then, is an intermediate, since the judge is so.  Now the judge restores equality; it is as though there were a line divided into unequal parts, and he took away that by which the greater segment exceeds the half, and added it to the smaller segment.  And when the whole has been equally divided, then they say they have 'their own' -- i.e. when they have got what is equal.  The equal is intermediate between the greater and the lesser line according to the mathematical proportion.  It is for this reason that it is called just (dikaion), because it is a division into two equal parts (dikha), just as if one were to call it dikaion; and the judge (dikastes) is one who bisects (dikhastes).  For when something is subtracted from one of two equals and added to the other, the other is in excess by these two; since if what was taken from the one had not been added to the other, the latter would have been in excess by one only.  | It therefore exceeds the intermediate by one, and the intermediate exceeds by one that from which something was taken.  By this from which has more, and what we must add to that which has less; we must add to the latter that by which the intermediate exceeds it, and subtract for the greatest that by which it exceeds the intermediate.  Let the lines AA', BB', CC' be equal to one another; form the line AA' let the segment AE have been subtracted from the line CC' let the segment CD have been added, so that the whole line DCC' exceeds the line EA' by the segment CD and the segment CF; therefore it exceeds the line BB' by the segment CD.  These names, both loss and gain, have come from voluntary exchange; for to have more than one's own is gaining, and to have less than one's original share is called losing, e.g. in buying and selling and in all other matters in which the law has left people free to make their own terms; but when they get neither more nor less but just what belongs to themselves, they say that they have their own and that they neither lose nor gain.  Therefore the just is intermediate between a sort of gain and a sort of loss, viz, those which are involuntary; it consists in having an equal amount before and after the transaction." 1132 a 25 - 1132 b 14.

                     A       E                 A'


                    B                            B'


            D     C      F                    C'



Justice is reciprocity according to Aristotle

"Some think that reciprocity is without qualification just, as the Pythagoreans said; for they defined justice without qualification as reciprocity.  Now 'reciprocity' fit neither distributive nor rectificatory justice-- yet people who want even the justice of Rhadamanthus to mean this:

Should a man suffer what he did, right justice would be done [an eye for an eye in other words]

-- for in many cases reciprocity and rectificatory justice are not in accord; e.g. (1) if an official has inflicted a wound, he should not be wounded in return, and if someone has wounded an official, he ought not to be wounded only but in punishment in addition.  Further, (2)  there is a great difference between a voluntary and an involuntary act.  But in associations for exchange this sort of justice [reciprocity] does hold men together-- reciprocity in accordance with a proportion and not on the basis of precisely equal return.  For it is by proportionate requital that the city holds together.  Men seek to return either evil for evil-- and if they cannot do so, they think their position mere slavery-- | or good for good--- and if they cannot do so there is no exchange that they hold together. "  1132 b 14 - 1132 b 33.

Aristotle's view of justice is one of 'giving people what they are due,' or a mean between getting more or less than they are due.

In example a fair exchange would be something like the following:

A and B are workers in different trades, and will normally be of different degrees of 'worth'.  Their products, therefore, will also have unequal worth, i.e. (this equation provided by Ross, and is not present in the text of Aristotle)

A = nB, C (what A makes, say, in an hour) will be worth n times as much as D (what B makes in an hour).  

A fair exchange will then take place if A gets nD and B gets 1 C;

 i.e. if A gives what it takes him an hour to make, in exchange for what it takes B n hours to make. 

We are responsible for bad as well as good actions. 1113 b 1.

Claiming that we ought to act justly, implies that we can act justly, or what is commonly called "ought implies can".  1113 b 6.

To be considered just or unjust, one must act on choice (voluntary not involuntary actions).  1136 a 2.

Choice is only possible in rational animals (humans).  1111 b 3.

When one finds pleasure in doing virtuous acts, it is clear one has attained a virtuous disposition.  1104 b 4.

Virtue as the mean between the extremes

"Virtue, then, is a state of character concerned with choice, lying in a mean, i.e. the mean relative to us,  |  this being determined by a rational principle, and by that principle by which the man of practical wisdom would determine it.  Now it is a mean between two vices, that which depends on excess and that which depends on defect; and again it is a mean because the vices respectively fall short of or exceed what is right in passions and actions, while virtue both finds and chooses that which is intermediate.  Hence in respect of what it is, i.e. the definition which states its essence, virtue is a mean, with regard to what is best and right an extreme.  But not every action nor passion admits of a mean; for some have names that already imply badness, e.g. spite, shamelessness, envy, and in the cases of actions adultery, theft, murder [.]"  1106 b 36 - 1107 a 15.

extreme (pain)


MEAN (virtue or excellence, arete)


extreme (pleasure)







piggishness/ self-indulgence


liberality (charity)



magnificence (live like an artist)





bad temper

good temper

 being too easy going











shame (quasi-virtue)

rectificatory justice

justice (reciprocal)

distributive justice

The mean is hard to obtain, and grasped by sense perception not reason

"That moral virtue is a mean, then, in what sense it is so, and that it is a mean between two vices, the one involving excess, and the other deficiency, and that it is such because its character is to aim at what is intermediate in passions and in actions has been sufficiently stated.  Hence also it is not easy task to be good.  For in everything it is no easy task to find the middle, e.g. to find the middle of a circle is not easy for everyone but for him that knows; so, too, anyone can get angry-- that is easy-- or give or spend money;  but to do this to the right person, to the right extent, at the right time, with the right motive, and in the right way, that is not for everyone, nor is it easy;  wherefore goodness is both rare and laudable and noble. [...]  But we must consider the things towards which we ourselves also are easily carried away; for some of us tend to be one thing, some to be another; and this will be recognizable from the pleasure and pain we feel.  We must drag ourselves away to the contrary extreme for we shall get into the intermediate state by drawing well away from error, as people do in straightening sticks that are bent.  Now in everything the pleasant or pleasure is most to be guarded against; for we do not judge it impartially.  We ought, then, to feel towards pleasure as the elders of the people felt towards Helen, and in all circumstances repeat their saying [Iliad iii 156-160]; for if we dismiss pleasure thus we are less likely to go astray.  It is by doing this, then, (to sum the matter up) that we shall best be able to hit the mean."  1109 a 25 - 1109 b 15.  


Habit is better seen as custom, or be accustomed, and not a mere automatic response.

"For this reason also the question is asked, whether happiness is to be acquired by learning or by habituation or some other sort of training, or comes in virtue of some divine providence or again by chance.    Now if there is any gift of the gods to men, it is reasonable that happiness should be god-given and most surely god-given of all human things inasmuch as it is the best.  But this question would perhaps be more appropriate to another inquiry; happiness seems, however, even if it is not god-sent but comes a result of virtue, and some process of learning or training, to be among the most godlike things; for that which is the prize and end of virtue seems to be the best thing in the world, and something godlike and blessed.  It will also on this view be generally shared; for all who are not maimed as regards their potentiality for virtue may win it by a certain kind of study and care.  But if it is better to be happy thus than by chance, it is reasonable that the facts should be so, since everything that depends on the action of nature is by nature as good as it can be, and similarly everything that depends on art or any rational cause, and especially if it depends on the best of all causes.  To entrust to chance what is greatest and most noble would be a very defective arrangement.  The answer to the question we are asking is plain also from the definition of happiness; for it has been said to be a virtuous activity of the soul, of a certain kind.  Of remaining goods, some must necessarily preexist as conditions of happiness, and others are naturally co-operative and useful as instruments.  And this will be found to agree with what we said at the outset [1096 a 16]; for we stated the end of political science to be the best end, and political science spends most of its pains on making the citizens to be of a certain character, viz. good and capable of noble acts.  It is natural, then, that we call neither ox nor horse nor any other of the animals happy; for none of them is capable of sharing in such an activity." 1099 b 10 - 1099 b 32

Can a man be called happy while he lives?

"Must on one at all, then, be called happy while he lives; must we, as Solon says, see the end?  Even if we are to lay down this doctrine, it is also the case that a man is happy when he is dead?  Or is not this quite absurd, especially for us who say that happiness is an activity? [...]  Now if we must see the end and only then call a man blessed, not as being blessed but as having been so before, surely this is a paradox, that when he is happy the attribute that belongs to him is not to be truly predicated of him because we do not will to call living men happy [.] [...] For no function of man has so much permanence as virtuous activities (these are thought to be more durable even than knowledge of the sciences), and of these themselves the most valuable are more durable because those who are blessed spend their life most readily most continuously in these; for this seems to be the reason why we do not forget them.  The attribute in question, then, will belong to the happy man, and he will be happy throughout his life; for always, or by preference to everything else, he will do and contemplate what is excellent, and he will bear the chances of life most nobly and altogether decorously, if he is 'truly good' and 'foursquare beyond approach'. [...]  If activities are, as we said, what determines the character of life, no blessed man can become miserable; for he will never do the acts that are hateful and mean.  For the man who is truly good and wise, | we think bears all the chances of life becomingly and always makes the best of circumstances, as a good general makes the best military use of the army at his command, and a good shoemaker makes the best shoes out of the hides that are given him; and so with all other craftsmen.  And is this is the case, the happy man can never become miserable-- though he will not reach blessedness, if he meets with fortunes like those of Priam.  Nor, again, is he many-colored and changeable; for neither will he be moved from his happy state easily or by any ordinary misadventures, but only by many great ones, nor, if he had many great misadventures, will he recover his happiness in a short time, but if at all, only in a long and complete one in which he has attained many splendid successes.  Why then should we not say that he is happy when active in accordance with complete virtue and is sufficiently equipped with external goods, nor for some chance period, but throughout a complete life? Or must we add 'and who is destined to live thus and die as befits his life'?  Certainly the future is obscure to us, while happiness, we claim, is an end and something in every way final.  If so, we shall call blessed those among living men in whom these conditions are, and are to be fulfilled-- but blessed men." 1100 a 1 - 1101 a 15


Book VIII 2-3, 5, 8

2. "The three kinds of friendship may perhaps be cleared up if we first come to know the object of love.  For not everything seems to be loved but only the lovable, and this is good, pleasant, or useful; but it would seem to be that by which some good or pleasure is produced that it is useful, so that it is the good and pleasant that are lovable as ends. Do men love, then, the good, or what is good for them? These sometimes clash.  So too with regard to the pleasant. Now it is thought that each loves what is good for himself, and the good is without qualification lovable, and what is good for each man is lovable for him; but each man loves not what is good for him but what seems good.  This however shall make no difference; we shall just have to say that this is "that -which seems lovable". Now there are three grounds on which people love:  of the love of lifeless objects we do not use the word 'friendship', for it is not mutual love, nor is there a wishing of good to the other (for it would surely be ridiculous to wish wine well; if one wishes anything for it, it is that it may keep, so that one may have it oneself); but to a friend we ought to wish what is good for his sake.  But to those who thus wish good we ascribe only goodwill, if the wish is not reciprocated; goodwill when it is reciprocal being friendship.  Or must we add 'when it is recognized'? [...]"

3. [...] "There are therefore three kinds of friendship, equal in number to the things that are lovable; for with respect to each there is a mutual and recognizable love, and those who love each other wish well to each other in that respect in which they love one another.  Now those who love each other for their utility do not love each other for themselves but in virtue of some good which they get from each other.  So too with those who love each other for the sake of pleasure; it is not for their character that men love ready-witted people, but because they find them pleasant.  Therefore those who love for the sake of utility love for the sake of what is good for themselves, and those who love for the sake of pleasure do so for the sake of what is pleasant to themselves, and not in so far as the other is the person loved but in so far as he is useful or pleasant.  And thus these friendships are only incidental; for it is not as being the man he is that the loved person is loved, but as providing some good or pleasure.  Such friendships, then, are easily dissolved, if the parties do not remain like themselves; for if the one party is no longer pleasant or useful the other ceases to love him. " [...]

5. [...] "The truest friendship, then, is that of the good, as we have frequently said; for that which is without qualification good or pleasant seems to be lovable and desirable, and for each person that which is good or pleasant to him; [...] And in loving a friend men love what is good for themselves; for the good man in becoming a friend becomes a good to his friend.  Each, then, both loves what is good  for himself, and makes an equal return in good will and in pleasantness, for friendship is said to be equality, and both of these are found most in the friendship of the good."

8. "Most people seem, owing to ambition, to wish to be loved rather than love; which is why most men love flattery; for the flatterer is a friend in an inferior position, or pretends to be such and to love more than he is loved; and being loved seems akin to being honored, and this is why most people aim at it.  But it seems to be not for its own sake that people choose honor, but incidentally. [...] Now since friendship depends more on loving, and it is those who love their friends that are praised, loving seems to be the characteristic virtue of friends, so that it is only those in whom this is found in due measure that are lasting friends, and only their friendship endures."

Friendship is reciprocity. 1159 b 25 - 1160 a 30.

When to break off friendships:

"Another question that arises is whether friendships should or should not be broken off when the other party does not remain the same. | Perhaps we may say that there is nothing strange in breaking off a friendship based on utility or pleasantness, when our friends no longer have these attributes.  For it was these attributes that we were the friends; and when these have failed it is reasonable to love no longer.  But one might complain of another if, when he is loved us for our usefulness or pleasantness, and pretended to love us for our character.  For, as we said at the outset [1162 b 23-25], most differences arise between friends when they are not friends in the spirit in which they think they are.  So when a man has deceived himself and has thought he was being loved for his character, when the other person was doing nothing of the kind, he must blame himself; but when he has been deceived by the pretences of the other person, it is just that he should complain with more justice than one does against people who counterfeit the currency, inasmuch as the wrongdoing is concerned with something more valuable.  But if one accepts another man as good, and he turns out badly and is seen to do so, must one still love him?  Surely it is impossible, since not everything can be loved, but only what is good.  [...]  But if one friend remained the same while the other became the better and far outstripped him in virtue should the latter treat the former as a friend?  Surely he cannot.  When the interval is great this becomes most plain, e.g. in the case of childish friendships;  if one remained a child in intellect while the other became a fully developed man, how could they be friends when they neither approved of the same things nor delighted in and were pained by the same things?"  1165 a 35 - 1165 b 28

Friendship is based on true self-love. 1166 a 1 and 1168 a 30

Only the good man should be a lover of himself.   1169 a 10

In order to be happy, men need friends.  1169 b 20

But you can have too many friends; one should limit the number of friends.  

"Presumably, then, it is well not to seek to have as many friends as possible, but as many as are enough for the purpose of living together; for it would seem actually impossible to be a great friend to many people.  This is why one cannot love several people; love is ideally a sort of exercise of friendship, and that can only be felt towards one person; therefore great friendship too can only be felt towards a few people." 1171 a 8- 1171 a 15

The essence of friendship is living together.

"For friendship is a partnership, and as a man is to himself, so is he to his friend; now in his own case of consciousness of his being desirable, and so therefore is the consciousness of his friend's being, and the activity of this consciousness is produced when they live together, so that it is natural to aim at this."  1172 a 1

Legislation is needed if the end be obtained (transition to the Politics). 1179 a 35