Summary: Ethics (page 5)

Spinoza begins by recalling that, according to his deterministic conception, there is no absolute—or in other words, free—will in the mind. Instead, the mind is determined to will this or that by a cause, which is itself determined by another cause, which in turn is determined by yet another, and so on ad infinitum ¹.

The same applies to the so-called faculties of understanding, desiring, and loving, which are therefore either purely fictitious or nothing more than metaphysical entities—that is, universals that we are accustomed to forming from particulars ².

In reality, what exists is not the will as a general faculty, but rather particular volitions that accompany specific ideas. As Spinoza puts it: The intellect and the will have with this idea or volition the same relation as stone has with this stone, or as man has with Peter and Paul ³.

It should be noted that by will, Spinoza does not mean desire (which he will address in the next section), but rather the faculty of affirming or denying the truth or falsity of something ⁴.

Furthermore, volitions themselves vanish, since an idea inherently contains its own negation or affirmation. Ideas are not mere images or representations that the mind then chooses to accept or reject—they carry within themselves their own assent.

Consider an example: it is not the will that refuses the idea of throwing oneself into the void; rather, the idea itself contains its own principle of persuasion (or refusal). Just as truth reveals itself by its own light or evidence, as we have already seen.

Thus, Spinoza can affirm:

In the mind there is no volition—that is, no affirmation or negation—apart from that which is inherent in the idea itself, insofar as it is an idea ⁵.

There is, therefore, no distinction between will and intellect. To understand an idea is to adhere to it or reject it, depending on the affirmation or negation it carries. It is the idea itself that imposes itself upon us—or, conversely, provokes our resistance.

And yet, it seems that some people sincerely adhere to false ideas. Spinoza denies this: they are not truly certain of the idea; at best, they merely lack doubt. Certainty is something positive—it is not merely the absence of doubt. Only a true idea can produce certainty.

In the same way, Spinoza dismisses other objections. For example, since Descartes, the will has been distinguished from the intellect on the grounds that the former is infinite while the latter is finite. Or that, without free will, we would be unable to choose between two ideas with the same force of assent—like Buridan’s ass, who allows himself to die because he is positioned equidistantly between hay and water.

Spinoza now begins to consider the practical consequences of the first two parts of his work. His doctrine offers a way to bring tranquillity to the soul in all circumstances, for it teaches that we act solely by God's command, that we participate in the divine nature, and that, ultimately, our supreme happiness consists in the knowledge of God alone ⁶.

Part III: Of the Affects

Affects refer to human passions and desires. It would be a mistake to consider them contrary to nature. On the contrary, since everything necessarily proceeds from the divine substance, everything is natural:

For the most part, those who have written about the affects seem to be dealing, not with natural things that follow the common laws of nature, but with things that are outside nature. They even seem to conceive of man in nature as an empire within an empire. For they believe that man disturbs the order of nature rather than follows it ⁷.

This is a profound error. On the contrary, nothing in nature occurs due to some defect within it. For nature is always the same and possesses everywhere one and the same virtue and power to act ⁸.

¹ Part I, prop. 15
² I, prop. 17
³ I, prop. 29
⁴ I, prop. 29, note
⁵ I, prop. 33, note 2