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A Resource Guide for Philosophy Students

Created by Jennifer Leslie Torgerson, MA

This page last modified:  October 14, 2012

© copyright, 1997 - present


School of Athens



1632 – 1677  CE





Baird and Kaufmann.  Philosophical Classics:  From Plato to Nietzsche, 2nd Edition. (Upper Saddle River, NJ:  Prentice Hall, 1997 [1994]).


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


__________,  A History of Western Philosophy:  Hobbes to Hume, 2nd Edition.  (San Diego, CA:  Harcourt Brace, 1980 [1952]).


Daniel Kolak.  The Mayfield Anthology of Western Philosophy.  (Mountain View, CA:  Mayfield Publishing, 1998).


Louis P. Pojman.  Classics of Philosophy.  (New York, NY:  Oxford University Press, 1998).


Baruch Spinoza.  Reflections and Maxims; Dagobert D. Runes, Editor.  (New York, NY:  Philosophical Library, 1965 [1951]).


Benedict de Spinoza.  On the Improvement of the Understanding, The Ethics, and Correspondence; Unabridged Elwes Translation.  (New York, NY:  Dover, 1955 [1883]).


T. V. Smith and Marjorie Grene.  Philosophers Speak for Themselves:  From Descartes to Locke.  (Chicago, IL: University of Chicago Press, 1967 [1940]).



The principle works of Spinoza


Principles of Philosophy (1663)

Political Treatise (Opera posthuma)

Short Treatise on God, Man and Well-Being (discovered in 1851)

The Ethics a demonstration according to Geometrical Order (Opera posthuma)

Theological-Political Treatise (1670) anonymously

Treatise on the Correction of the Understanding (Opera posthuma)


The Ethics

Part I: Concerning God


1. By that which is self-caused, I mean that of which the essence involves existence, or that of which the nature is only conceivable as existent.

2. A thing is called finite after its kind, when it can be limited by another thing of the same nature; for instance, a body is called finite because we always conceive another greater body. So, also, a thought is limited by another thought, but a body is not limited by thought, nor a thought by body.

3. By substance, I mean that which is in itself, and is conceived through itself: in other words, that of which a conception can be formed independently of any other conception.

4. By attribute, I mean that which the intellect perceives as constituting the essence of a substance.

5. By mode, I mean the modifications of substance, or that which exists in, and is conceived through, something other than itself.

6. By God, I mean a being absolutely infinite-- that is, a substance consisting in infinite attributes, of which each expresses eternal and infinite essentiality.

Explanation-- I say absolutely infinite, not infinite after its kind: for, of a thing infinite only after its kind, infinite attributes may be denied; but that which is absolutely infinite, contains in its essence whatever expresses reality, and involves no negation.

7. That thing is called free, which exists solely by the necessity of its own nature, and of which the action is determined by itself alone. On the other hand, that thing is necessary, or rather constrained, which is determined by something external to itself to a fixed and definite method of existence or action.

8. By eternity I mean existence itself, in so far as it is conceived necessarily to follow solely from the definition of that which is eternal.

Explanation-- Existence of this kind is conceived as an eternal truth, like the essence of a thing, and, therefore, cannot be explained by means of continuance or time, though continuance may be conceived without a beginning or end.



1. Everything which exists, exists either in itself or in something else.

2. That which cannot be conceived through anything else, must be conceived through itself.

3. From a given definite cause an effect necessarily follows; and, so on the other hand, if no definite cause be granted, it is impossible that an effect can follow

(ex nihilo nihil fit- from nothing nothing comes; to take away the cause is to take away the effect. Universal causation- the view that every event has a cause.)

4. The knowledge of an effect depends on and involves the knowledge of a cause.

5. Things which have nothing in common cannot be understood, the one by mean of the other; the conception of one does not involve the conception of the other.

6. A true idea must correspond with it’s ideate or object.

(Spinoza holds the correspondence theory of truth.)

7. If a thing can be conceived as non-existing, its essence does not involve existence.



(See the Solomon textbook for the proofs for these propositions)

1. Substance is by nature prior to its modifications.

2. Two substances, whose attributes are different, have nothing in common

3. Things which have nothing in common cannot be one the cause of the other.

4. Two or more distinct things are distinguished one from the other, either by the difference of the attributes of substance, or by the difference of their modifications.

5. There cannot exist in the universe two or more substances having the same nature or attribute.

6. One substance cannot be produced by another substance.

7. Existence belongs to the nature of substance.

8. Every substance is necessarily infinite

9. The more reality or being a thing has the greater the number of its attributes.

10. Each particular attribute of the one substance must be conceived through itself.

11. God, or substance, consisting of infinite attributes, of which each expresses eternal and infinite essentiality, necessary exists.

Proof-- If this be denied, conceive, if possible, that God does not exist: then his essence does not involve existence. But this (by prop 7) is absurd. Therefore God necessarily exists.

NOTE that Spinoza gives more proofs for the existence of God here at Prop 11.

12. No attribute of substance can be conceived from which it would follow that substance can be divided.

13. Substance absolutely infinite is indivisible.

14. Besides God no substance can be granted or conceived.

15. Whatever is, is in God, and without God, nothing can be or be conceived.

16. From the necessity of the divine nature must follow an infinite number of things in infinite ways-- that is, all things which can fall within the sphere of infinite intellect.

17. God acts solely by the laws of his own nature, and is not constrained by anyone.

18. God is the indwelling and not the transient cause of all things.

19. God, and all the attributes of God, is eternal.

20. The existence of God and his essence are one and the same.

Proof-- God (by the last prop) and all his attributes are eternal, that is (by def. 8) each of his attributes expresses existence. Therefore the same attributes of God which explain his eternal essence, explain at the same time his existence. Wherefore God's existence and God's essence are one and the same. Q.E.D. (it is proven)

21. All things which follow from the absolute nature of any attribute of God must always exist and be infinite, or, in other words, are eternal and infinite through the said attribute.

22. Whatsoever follows from any attribute of God, is so far as it is modified by a modification, which exists necessarily and as infinite, through the said attribute, must also exist necessarily as infinite.

23. Every mode, which exists both necessarily and as infinite, must necessarily follow either from the absolute nature of some attribute of God, or from an attribute modified by a modification which exists necessarily, and as infinite.

24. The essence of things produced by God does not involve existence

Corollary-- Hence it follows that God is not only the cause of things coming into existence, that is, in scholastic phraseology; God is the cause of the being of things (essendi rerum). [...] God must be the sole cause, inasmuch as to him alone does existence appertain.

25. God is the efficient cause not only of the existence of things, but also of their essence.

32. Will cannot be called a free will, but only a necessary cause.

Corollary 1- Hence it follows, first, that God does not act according to freedom of will.

Corollary 2- It follows, secondly, that will and intellect stand in the same relation to the nature of God, as do motion, and rest, and absolutely all natural phenomena, which must be conditioned by God.

34. God's power is identical with his essence.

Substance is that which can be conceived alone. Substance therefore needs nothing else in order to exist.
Spinoza also will argue that this substance is in fact God (or the Absolute)

Some Attributes, or essential qualities of substance, are self-caused, eternal, existence, infinite, necessary,
efficient cause.

No two substances can have the same attributes. No substance can cause another substance to exist.
Only one substance exists.

Mode or modifications of substance are those things which cannot be conceived alone, but must be
conceived through something else.

Consider thought. It cannot be thought of as being alone, without a thinker to have the thought. The idea of thought, is conceived (or thought of) through something else (namely the one doing the thinking).

Modifications do not exist. Only substance (that which is conceived through itself) exists. Modes are conceived through substance, in the way that in the analogy, thought is conceived through a thinker.

Examples of modes are mind and body. The human mind and human body are modes of substance, or aspects of the Absolute. All thinking mode is the internal relation of God, and all extended
mode is the external relation of God. Minds and bodies do not exist;
they are the modes or aspects of that which does exist.

What I truly want you to understand about Spinoza is his Double
Aspect Theory and criticism of Descartes. You need to
know that there is only one eternal infinite substance, and that this
is the Absolute. What dualists like Descartes call substances cannot
be substances, since they cannot be conceived alone, but only through something else.

This dualism of Descartes left him caught in solipsism. Solipsism is the view that all one can know is their own ideas, and not if anything real corresponds to them.

Truth is a matter of correspondence to reality. True ideas or true statements match or correspond to a true state of affairs. In order to verify this correspondence it is necessary that the idea in the subject be compared to the object. But Descartes' separate and distinct substances of mind and body do not permit this kind of verification. Descartes is caught in his mind, thinking about the doubt, and he cannot be certain if any of his ideas correspond to anything real in the external world of the bodily mode. Descartes is caught in solipsism.

Another issue in Spinoza's text involved free will, the fact
that the Absolute is not "free". Freedom according to Spinoza meant
that things were not determined by another, and that one could do
what was necessarily determined by their own nature. Will according
to Spinoza cannot be ever considered a free cause, but always a
determined one. Hence the Absolute does not have free will as we
know it. The Absolute is not forced to do things by another's nature,
only its own, hence it is not being coerced.

Think of God as being the total sum of Nature. This is the Absolute.
Spinoza is a pantheist. He believes that all is God. There is no
transcendence from the Creation. There isn't a Creation.
The Absolute is the indwelling, not the transient cause of the universe.
All existence is eternal. All substance is infinite.
This is truly only one substance, since no two substances can
share the same attributes. Therefore, there is only one substance,
the Absolute.

Double-aspect theory (identity theory)

Spinoza, a Dutch philosopher, held the view that mind and body were just two aspects of the same one reality. This is pantheistic, or the belief that all is God. Mental reality is subjective or internal, and bodily reality is objective or external. We know our inner life intimately, but we only know the physical world second-hand through sense experience.  Spinoza was a rationalist.

For Spinoza, the mind and the body are aspects of the Absolute. The mind is the thinking mode, and the body is the extended mode. Hence, there isn't a separation of mind-body for Spinoza like there was for Descartes' dualism. [Descartes cannot account for the correspondence of idea to the objects they are ideas about]

Mind and body are a result of the efficient causality of the Absolute according to Spinoza. Minds do not affect bodies and bodies do not affect minds.

[By not separating mind and body, Spinoza establishes a foundation for the correspondence of ideas and objects.]

Mind and body are not substance. Only God is substance. This is the logical outcome of the definition of substance as that which is conceived through itself.

Critique of Double Aspect Theory

Spinoza too has relied on a priori concepts not accepted by empiricists (nor all rationalists).  Double Aspect theory is thought to be a crude reductionism, in that it reduces what dualists call mind substance and body substance to nothing more than mere aspects of another more real substance.  Mind and body are merely consequences of the substantial causal activity. Only God is seen to be "free” according to Spinoza, hence everything in the universe is determined by the Absolute's nature, and it seems that even His nature is necessary and determinate.  (Spinoza thought that God did not have limit, even though He is extended.  He is simple, and perfect, and cannot have parts, nor limitations, hence His necessary nature (that He is simple, etc.) is not a limitation).