Spinoza
The Emendation of the Intellect
“A short, difficult, but fascinating discourse on method, was first published in Spinoza’s Opera posthuma in 1677. But as the editors of that collection tell us in their preface, both its style and its content show it to be one of Spinoza’s earliest works…a draft of it must have existed at least by early in 1662, and quite likely Spinoza wrote it before that.”
– Edwin Curley (editor & translator)
The Collected Works of Spinoza, Volume I
a few selections from the text:
[50]
Let us begin, therefore, from the first part of the Method, which is, as we have said, to distinguish and separate true ideas from all other perceptions, and to restrain the mind from confusing false, fictitious and doubtful ideas with true ones. It is my intention to explain this fully here, so as to engage my Readers in the thought of a thing so necessary, and also because there are many who doubt even true ideas from not attending to the distinction between a true perception and all others. So they are like men who, when they were awake, used not to doubt that they were awake, but who, after they once thought in a dream that they were certainly awake (as often happens), and later found that to be false, doubted even of their waking states. This happens because they have never distinguished between the dream and the waking state.

Rembrandt, 1632
[57]
It remains now to note also those things that are supposed in Problems. This sometimes happens even concerning impossible things. E.g., when we say “Let us suppose that this burning candle is not now burning, or let us suppose that it is burning in some imaginary space, or where there are no bodies.” Things like this are sometimes supposed, although this last is clearly understood to be impossible. But when this happens, nothing at all is feigned. For in the first case I have done nothing but recall to memory another candle that was not burning (or I have conceived this candle without the flame), and what I think about that candle, I understand concerning this one, so long as I do not attend to the flame.
In the second case, nothing is done except to abstract the thoughts from the surrounding bodies so that the mind directs itself toward the sole contemplation of the candle, considered in itself alone, so that afterwards it infers that the candle has no cause for its destruction. So if there were no surrounding bodies, this candle, and its flame, would remain immutable, or the like. Here, then, there is no fiction, but true and sheer assertions.

Gerhard Richter, 1982
[69]
As for what constitutes the form of the true, it is certain that a true thought is distinguished from a false one not only by an extrinsic, but chiefly by an intrinsic denomination. For if some architect conceives a building in an orderly fashion, then although such a building never existed, and even never will exist, still the thought of it is true, and the thought is the same, whether the building exists or not. On the other hand, if someone says, for example, that Peter exists, and nevertheless does not know that Peter exists, that thought, in respect to him is false, or, if you prefer, is not true, even though Peter really exists. Nor is this statement, Peter exists, true, except in respect to him who knows certainly that Peter exists.
[70]
From this it follows that there is something real in ideas, through which the true are distinguished from the false. This will now have to be investigated, so that we may have the best standard of truth (for we have said that we must determine our thoughts from the given standard of a true idea, and that method is reflective knowledge), and may know the properties of the intellect. Nor must we say that this difference arises from the fact that the true thought is knowing things through their first causes. In this, indeed, it differs greatly from the false, as I have explained above. For that Thought is also called true which involves objectively the essence of some principle that does not have a cause, and is known through itself and in itself.

Monet, 1894
[99]
As for order, to unite and order all our perceptions, it is required, and reason demands, that we ask, as soon as possible, whether there is a certain being, and at the same time, what sort of being it is, which is the cause of all things, so that its objective essence may also be the cause of all our ideas, and then our mind will (as we have said) reproduce Nature as much as possible. For it will have Nature’s essense, order, and unity objectively.
From this we can see that above all it is necessary for us always to deduce all our ideas from Physical things, or from the real beings, proceeding, as far as possible, according to the series of causes, from one real being to another real being, in such a way that we do not pass over to abstractions and universals, neither inferring something real from them, nor inferring them from something real. For to do either interferes with the true progress of the intellect.
[100]
But note that by the series of causes and of real beings I do not here understand the series of the singular, changeable things, but only the series of fixed and eternal things. For it would be impossible for human weakness to grasp the series of the singular, changeable things, not only because there are innumerably many of them, but also because of the infinite circumstances in one and the same thing, any of which can be the cause of its existence or nonexistence. For their existence has no connection with their essence, or (as we have already said) is not an eternal truth.
[101]
But there is also no need for us to understand their series. The essences of singular, changeable things are not to be drawn from their series, or order of existing, since it offers us nothing but extrinsic denominations, relations, or at most, circumstances, all of which are far from the inmost essence of things. That essence is to be sought only from the fixed and eternal things, and at the same time from the laws inscribed in these things, as in their true codes, according to which all singular things come to be, and are ordered. Indeed these singular, changeable things depend so intimately, and (so to speak) essentially, on the fixed things that they can neither be nor be conceived without them. So although these fixed and eternal things are singular, nevertheless, because of their presence everywhere, and most extensive power, they will be to us like universals, or genera of the definitions of singular, changeable things, and the proximate causes of all things.

Anselm Kiefer, Ash Flower, 1983
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