The Book in 3 Sentences

1. There is only one substance - God or Nature - and everything that exists, including our minds and bodies, follows from it with strict necessity.
2. Our belief in free will and divine purpose is simply ignorance of the causes that determine us.
3. Freedom is not escaping the passive emotions that push us around but understanding them, turning confused ideas into adequate ones until an emotion ceases to be a passion.

Overview & Impressions

I found Ethics to be very intellectually dense but worth the effort. Spinoza builds his entire non-dualist, panpsychist system geometrically, from definitions and axioms through propositions and proofs, so you can clearly see how each idea rests on the last. The proofs are sometimes hard to follow, and occasionally it felt like he had reached a conclusion first and constructed the proof retrospectively to lead to a certain intuition. The digressions where he expands on an idea in a more digestible way were helpful in understanding the implications of his propositions. I'm a big fan of his ideas, especially on behaviour, desire and free will, and the intellectual rigour is appreciated despite some of the later parts feeling a bit weaker. A fairly demanding read but insightful and paradigm shifting.

Top Quotes

Men think themselves free inasmuch as they are conscious of their volitions and desires, and never even dream, in their ignorance, of the causes which have disposed them so to wish and desire.

We are in many ways driven about by external causes, and like waves of the sea driven by contrary winds we toss to and fro unwitting of the issue and of our fate.

He, who strives to conquer hatred with love, fights his battle in joy and confidence; he withstands many as easily as one, and has very little need of fortune’s aid.

Summary, Quotes & Notes

I

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.

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

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.

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

Nothing in the universe is contingent, but all things are conditioned to exist and operate in a particular manner by the necessity of the divine nature.

Men think themselves free inasmuch as they are conscious of their volitions and desires, and never even dream, in their ignorance, of the causes which have disposed them so to wish and desire.

For example, if a stone falls from a roof on to someone's head, and kills him, they will demonstrate by their new method, that the stone fell in order to kill the man; for, if it had not by God's will fallen with that object, how could so many circumstances (and there are often many concurrent circumstances) have all happened together by chance? Perhaps you will answer that the event is due to the facts that the wind was blowing, and the man was walking that way. "But why," they will insist, "was the wind blowing, and why was the man at that very time walking that way?" If you again answer, that the wind had then sprung up because the sea had begun to be agitated the day before, the weather being previously calm, and that the man had been invited by a friend, they will again insist: "But why was the sea agitated, and why was the man invited at that time?" So they will pursue their questions from cause to cause, till at last you take refuge in the will of God-in other words, the sanctuary of ignorance. So, again, when they survey the frame of the human body, they are amazed; and being ignorant of the causes of so great a work of art, conclude that it has been fashioned, not mechanically, but by divine and supernatural skill, and has been so put together that one part shall not hurt another.

And philosophers are not lacking who have persuaded themselves, that the motion of the heavenly bodies gives rise to harmony - all of which instances sufficiently show that everyone judges of things according to the state of his brain, or rather mistakes for things the forms of his imagination.

It is commonly said: "So many men, so many minds; everyone is wise in his own way; brains differ as completely as palates." All of which proverbs show, that men judge of things according to their mental disposition, and rather imagine than understand: for, if they understood phenomena, they would, as mathematicians attest, be convinced, if not attracted, by what I have urged.

For the perfection of things is to be reckoned only from their own nature and power; things are not more or less perfect, according as they delight or offend human senses, or according as they are serviceable or repugnant to mankind. To those who ask why God did not so create all men, that they should be governed only by reason, I give no answer but this: because matter was not lacking to him for the creation of every degree of perfection from highest to lowest; or, more strictly, because the laws of his nature are so vast, as to suffice for the production of everything conceivable by an infinite intelligence, as I have shown in Prop. xvi.

II

The order and connection of ideas is the same as the order and connection of things.

Besides these two kinds of knowledge, there is, as I will hereafter show, a third kind of knowledge, which we will call intuition. This kind of knowledge proceeds from an adequate idea of the absolute essence of certain attributes of God to the adequate knowledge of the essence of things.

It is in the nature of reason to perceive things under a certain form of eternity (sub quadam aeternitatis specie).

In the mind there is no absolute or free will; but the mind is determined to wish this or that by a cause, which has also been determined by another cause, and this last by another cause, and so on to infinity.

III

I shall consider human actions and desires in exactly the same manner, as though I were concerned with lines, planes, and solids.

Mind and body are one and the same thing, conceived first under the attribute of thought, secondly, under the attribute of extension.

Everything, in so far as it is in itself, endeavours to persist in its own being.

Desire is appetite with consciousness thereof.

It is thus plain from what has been said, that in no case do we strive for, wish for, long for, or desire anything, because we deem it to be good, but on the other hand we deem a thing to be good, because we strive for it, wish for it, long for it, or desire it.

All emotions are attributable to desire, pleasure, or pain.

It is evident from what I have said, that we are in many ways driven about by external causes, and that like waves of the sea driven by contrary winds we toss to and fro unwitting of the issue and of our fate.

Appetite is the essence of man, in so far as it is determined to act in a way tending to promote its own persistence.

Whether a man be conscious of his appetite or not, it remains one and the same appetite.

Pleasure is the transition of a man from a less to a greater perfection.

Pain is the transition of a man from a greater to a less perfection.

Contempt is the conception of anything which touches the mind so little, that its presence leads the mind to imagine those qualities which are not in it rather than such as are in it.

Love is pleasure, accompanied by the idea of an external cause.

Hatred is pain, accompanied by the idea of an external cause.

Hope is an inconstant pleasure, arising from the idea of something past or future, whereof we to a certain extent doubt the issue.

Fear is an inconstant pain arising from the idea of something past or future, whereof we to a certain extent doubt the issue.

Confidence is pleasure arising from the idea of something past or future, wherefrom all cause of doubt has been removed.

Humility is pain arising from a man's contemplation of his own weakness of body or mind.

Emotion, which is called a passivity of the soul, is a confused idea, whereby the mind affirms concerning its body, or any part thereof, a force for existence (existendi vis) greater or less than before, and by the presence of which the mind is determined to think of one thing rather than another.

The mind passes to greater or less perfection, when it happens to affirm concerning its own body, or any part thereof, something involving more or less reality than before. When, therefore, I said above that the power of the mind is increased or diminished, I merely meant that the mind had formed of its own body, or of some part thereof, an idea involving more or less of reality, than it had already affirmed concerning its own body.

IV

Human infirmity in moderating and checking the emotions I name bondage: for, when a man is a prey to his emotions, he is not his own master, but lies at the mercy of fortune: so much so, that he is often compelled, while seeing that which is better for him, to follow that which is worse.

Nature does not work with an end in view.

As for the terms good and bad, they indicate no positive quality in things regarded in themselves, but are merely modes of thinking, or notions which we form from the comparison of things one with another.

An emotion can only be controlled or destroyed by another emotion contrary thereto, and with more power for controlling emotion.

"The better path I gaze at and approve, The worse - I follow."

Virtue is nothing else but action in accordance with the laws of one's own nature.

But that a man, from the necessity of his own nature, should endeavour to become non-existent, is as impossible as that something should be made out of nothing, as everyone will see for himself, after a little reflection.

No virtue can be conceived as prior to this endeavour to preserve one's own being.

There is no individual thing in nature, which is more useful to man, than a man who lives in obedience to reason.

What we have just shown is attested by experience so conspicuously, that it is in the mouth of nearly everyone: "Man is to man a God." Yet it rarely happens that men live in obedience to reason, for things are so ordered among them, that they are generally envious and troublesome one to another.

The highest good of those who follow virtue is common to all, and therefore all can equally rejoice therein.

He, who strives to conquer hatred with love, fights his battle in joy and confidence; he withstands many as easily as one, and has very little need of fortune's aid.

"The unhappy are comforted by finding fellow-sufferers."

A free man thinks of death least of all things; and his wisdom is a meditation not of death but of life.

V

An emotion, which is a passion, ceases to be a passion, as soon as we form a clear and distinct idea thereof.

For instance, if a man sees that he is too keen in the pursuit of honour, let him think over its right use, the end for which it should be pursued, and the means whereby he may attain it. Let him not think of its misuse, and its emptiness, and the fickleness of mankind, and the like, whereof no man thinks except through a morbidness of disposition.

The intellectual love of the mind towards God is that very love of God whereby God loves himself, not in so far as he is infinite, but in so far as he can be explained through the essence of the human mind regarded under the form of eternity.

In this life, therefore, we primarily endeavour to bring it about, that the body of a child, in so far as its nature allows and conduces thereto, may be changed into something else capable of very many activities, and referable to a mind which is highly conscious of itself, of God, and of things.

Blessedness is not the reward of virtue, but virtue itself; neither do we rejoice therein, because we control our lusts, but, contrariwise, because we rejoice therein, we are able to control our lusts.

Whereas the wise man, in so far as he is regarded as such, is scarcely at all disturbed in spirit, but, being conscious of himself, and of God, and of things, by a certain eternal necessity, never ceases to be, but always possesses true acquiescence of his spirit.

If the way which I have pointed out as leading to this result seems exceedingly hard, it may nevertheless be discovered. Needs must it be hard, since it is so seldom found. How would it be possible, if salvation were ready to our hand, and could without great labour be found, that it should be by almost all men neglected? But all things excellent are as difficult as they are rare.