Refutation Of Idealism
Descartes inferred from his cogito argument that mind and body were separate in substance, which meant that the first could exist apart from the second. Bound up with this was the view that I am immediately aware of myself as a mind, but need to infer the existence of material things, which is in principle open to doubt. A great many philosophers have subscribed to this opinion, but Kant thought he could show it to be definitively false. In order to say that my inner experiences come one before another I need to observe them against a permanent background, and this can only be a background of external objects, for there is nothing permanent in the flow of inner experience. As Kant put it in the second edition [of Critique Of Pure Reason], in which he transposed the argument to the discussion of existence in connection with the postulates of empirical thought, "The mere, but empirically determined, consciousness of my own existence proves the existence of objects in space outside me."
--W.H. Walsh, Kant, Immanuel, The Encyclopedia Of Philosophy (Collier-Macmillan)
I bolded what I think is the crucial passage. I'm not sure I understand either half of its argument, or why I should find the argument persuasive, though I don't have a clear objection to it either. Why does time need a background of permanence? And why can't inner experience contain anything permanent? And also, what's "external" and what's "internal"? While Descartes would say that initially (until we've gone through his own arguments) we can't know that the objects we observe are actually outside the mind (rather than being inventions or hallucinations or dreams etc.), Kant seems to be arguing that because the objects are permanent, they must be outside the mind; but that seems circular. Why can't you just say that some of what's "in" the mind can be "permanent"? And what does "permanent" mean here?
The Critique is online, and I went to this section late at night a couple of nights ago and wasn't making headway, which is why I ran to the Encyclopedia for a paraphrase. Maybe I'll try again. Or go to Strawson. The reason I'm looking at it in the first place is to make sense of a couple of passages in Chapter 1, "The Invention Of The Mind," in Richard Rorty's Philosophy And The Mirror Of Nature (pp 20-23):
Kant and Strawson have given convincing arguments that we can only identify mental states as states of spatially located persons.* Since we have given up "mind-stuff," we are bound to take these arguments seriously. This brings us almost full-circle, for now we want to know what sense it makes to say that some states of a spatial entity are spatial and some are not. It is no help to be told that these are its functional states - for a person's beauty and his build and his fame and his health are functional states, yet intuition tells us that they are not mental states either.
. . .
The notion of mental entities as nonspatial and of physical entities as spatial, if it makes any sense at all, makes sense for particulars, for subjects of predication, rather than for the possession of properties by such subjects. We can make some dim sort of pre-Kantian sense out of bits of matter and bits of mind-stuff, but we cannot make any post-Kantian sense out of spatial and nonspatial states of spatial particulars. We get a vague sense of explanatory power when we are told that human bodies move as they do because they are inhabited by ghosts, but none at all when we are told that persons have nonspatial states.
(I don't think Rorty is arguing here that it makes more sense to say that persons have spatial states. What he's doing is trying to make us doubt the idea that there's some intuitive way that everybody naturally divides out the mental from the physical and that the latter's being "spatial" and the former's being "nonspatial" are where we make the divide. He says that we only start dividing in this "intuitive" way if we join a philosophical tradition that started with Descartes and that he sees as now [1979] thoroughly unraveling.)
*Rorty cites Kant's "Refutation of Idealism" in Critique Of Pure Reason and P.F. Strawson's Individuals chap. 2 and Strawson's The Bounds Of Sense pp 162ff.
--W.H. Walsh, Kant, Immanuel, The Encyclopedia Of Philosophy (Collier-Macmillan)
I bolded what I think is the crucial passage. I'm not sure I understand either half of its argument, or why I should find the argument persuasive, though I don't have a clear objection to it either. Why does time need a background of permanence? And why can't inner experience contain anything permanent? And also, what's "external" and what's "internal"? While Descartes would say that initially (until we've gone through his own arguments) we can't know that the objects we observe are actually outside the mind (rather than being inventions or hallucinations or dreams etc.), Kant seems to be arguing that because the objects are permanent, they must be outside the mind; but that seems circular. Why can't you just say that some of what's "in" the mind can be "permanent"? And what does "permanent" mean here?
The Critique is online, and I went to this section late at night a couple of nights ago and wasn't making headway, which is why I ran to the Encyclopedia for a paraphrase. Maybe I'll try again. Or go to Strawson. The reason I'm looking at it in the first place is to make sense of a couple of passages in Chapter 1, "The Invention Of The Mind," in Richard Rorty's Philosophy And The Mirror Of Nature (pp 20-23):
Kant and Strawson have given convincing arguments that we can only identify mental states as states of spatially located persons.* Since we have given up "mind-stuff," we are bound to take these arguments seriously. This brings us almost full-circle, for now we want to know what sense it makes to say that some states of a spatial entity are spatial and some are not. It is no help to be told that these are its functional states - for a person's beauty and his build and his fame and his health are functional states, yet intuition tells us that they are not mental states either.
. . .
The notion of mental entities as nonspatial and of physical entities as spatial, if it makes any sense at all, makes sense for particulars, for subjects of predication, rather than for the possession of properties by such subjects. We can make some dim sort of pre-Kantian sense out of bits of matter and bits of mind-stuff, but we cannot make any post-Kantian sense out of spatial and nonspatial states of spatial particulars. We get a vague sense of explanatory power when we are told that human bodies move as they do because they are inhabited by ghosts, but none at all when we are told that persons have nonspatial states.
(I don't think Rorty is arguing here that it makes more sense to say that persons have spatial states. What he's doing is trying to make us doubt the idea that there's some intuitive way that everybody naturally divides out the mental from the physical and that the latter's being "spatial" and the former's being "nonspatial" are where we make the divide. He says that we only start dividing in this "intuitive" way if we join a philosophical tradition that started with Descartes and that he sees as now [1979] thoroughly unraveling.)
*Rorty cites Kant's "Refutation of Idealism" in Critique Of Pure Reason and P.F. Strawson's Individuals chap. 2 and Strawson's The Bounds Of Sense pp 162ff.