There is a passage when Descartes is replying to an Objection where you can see the Modern concept of an 'idea' struggling to take shape. (Meditations and Replies, First Objections, Cottingham p. 132-133.)
Caterus argues that he doesn't understand all this business about ideas. All an idea is, he says, as Descartes presents it, is just another way of talking about ordinary things.
It is in his reply that Descartes grapples with expressing his new invention, his new notion of an idea which is that of something separate from the thing of which it is an idea, an item that lives in the mind, related to the thing of which it is an idea, but not simply an aspect thereof.
The discussion is cast in the terminology of 'objective existence', which is the scholastic mode. Things were said to have 'objective reality' in the intellect in so far as the intellect was understanding them, thinking about them. This was reality in virtue of being the object of the intellect's activities. It is not a very strong form of reality!
Kenny puts it like this.
When we start thinking of the sun, we can think of this as a change in us, or as a change in the sun, for it is both.
As far as the sun is concerned, it changes from not being thought about to being thought about.
This was expressed by the scholastics by saying that the sun when we were thinking about it was 'objectively in the understanding'. They meant by this to refer to a property of the sun.
But Descartes seems to be thinking of what is 'objectively in the understanding' as something distinct. He seems to be saying there is the sun on the one hand and on the other there is something in the mind when we think of the sun. - two things, not one thing with a certain property.
His critic says:
'What is an idea? It is the thing thought of itself in so far as that is "objectively in the understanding." But what is "existing in the understanding"? As I was taught, it is simply being the object of an act of thought, which is merely an external attribute of the thing and adds no reality to it.'
Descartes, Meditations, First Objections, (Johan de Kater). I use here the translation used by Kenny, Descartes, p.115. (Cottingham p.132.)
Descartes replies:
'Now I wrote that an idea is the thing which is thought of in so far as it has objective being in the intellect. But to give me an opportunity of explaining these words more clearly the objector pretends to understand them in quite a different way from that in which I used them. "Objective being in the intellect", he says, "is simply the determination of an act of the intellect by means of an object, and this is merely an extraneous label which adds nothing to the thing itself." Notice here that he is referring to the thing itself as if it were located outside the intellect, and in this sense "objective being in the intellect" is certainly an extraneous label; but I was speaking of the idea, which is never outside the intellect, and in this sense, "objective being" simply means being in the intellect in the way in which objects are normally there. for example, if anyone asks what happens to the sun through its being objectively in my intellect, the best answer is that nothing happens to it beyond the application of an extraneous label which does indeed " determine an act of the intellect by means of an object". But if the question is about what the idea of the sun is, and we answer that it is the thing that is thought of, in so far as it has objective being in the intellect, no one will take this to be the sun itself with this extraneous label applied to it. "Objective being in the intellect" will not here mean "the determination of an act of the intellect by means of an object", but will signify the objects being the intellect in the way in which its objects are normally there. By this I mean that the idea of the sun is the sun itself existing in the intellect - not of course formally existing, as it does in the heavens, but objectively existing, i.e. in the way in which objects normally are in the intellect. Now this mode of being is of course much less perfect than that possessed by things which exist outside the intellect; but, as I did explain, it is not therefore simply nothing.'
Descartes, Meditations, First Replies; Cottingham p. 132,3.
![]() | ![]() |