Indirect Realism

Indirect Realism The immediate objects of perception are mind-dependent objects that are caused by and represent mind-independent objects John Locke, Rene Descartes, David Hume, Bertrand Russell

Descartes Indirect Realism"To discover the nature of our ideas the better, and to discourse of the intelligibly, it will be convenient to distinguish them, as they are ideas of perceptions in our minds, and as they are modifications of matter in the bodies that cause such perceptions in us; that so we may not think (as perhaps usually is done) that they are exactly images and resemblances of something inherent in the subject; most of those [of sensation] being in the mind no more the likeness of something existing without us...Whatsoever the mind perceives in itself, or is the immediate object of perception, thought, or understanding that I call idea; and the power to produce any idea in our mind, I call the quality of the subject wherein that power is." (Meditation 3)

Descartes Indirect Realism The images produced by the physical body in our mind are known, by Descartes, as ideas The power to produce these ideas in our minds is a quality of the physical body

Locke's Indirect Realism"Whatsoever the mind perceives in itself, or is the immediate object of perception, thought, or understanding, that I call idea; and the power to produce any idea in our mind I call a quality of the subject wherein that power is. Thus a snowball having the power to produce in us the ideas of white, cold, and round, as they are in the snowball, I call qualities; and as they are sensation or perceptions in our understandings, I call them ideas;"

Locke's Indirect Realism The perceptions or sensations of white, cold and round are ideas The powers of the snowball to produce the sensations of white, cold and round are qualities

Hume's Indirect Realism"It seems clear that we humans are naturally, instinctively inclined to trust our senses, and that without any reasoning—indeed, almost before the use of reason—we take it that there is an external universe that doesn’t depend on our perceiving it and would have existed if there had never been any perceiving creatures or if we had all been annihilated. Even the animals are governed by a similar opinion, and maintain this belief in external objects in all their thoughts, plans and actions. It also seems clear that when men follow this blind and powerful instinct of nature they always suppose that the very images that their senses present to them are the external objects that they perceive; it never crosses their minds that sensory images are merely representations of external objects. This very table that we see as white and feel as hard is believed to exist independently of our perception, and to be something external to our mind, which perceives it. Our presence doesn’t bring it into existence, and our absence doesn’t annihilate it. It stays in existence (we think), complete and unchanging, independent of any facts about intelligent beings who perceive it or think about it. But the slightest philosophy is enough to destroy this basic belief that all men have. For philosophy teaches us that images (or perceptions) are the only things that can ever be present to the mind, and that the senses serve only to bring these images before the mind and cannot put our minds into any immediate relation with external objects. The table that we see seems to shrink as we move away from it; but the real table that exists independently of us doesn’t alter; so what was present to the mind wasn’t the real table but only an image of it. These are the obvious dictates of reason; and no-one who thinks about it has ever doubted that when we say ‘this house’ and ‘that tree’ the things we are referring to are nothing but perceptions in the mind—fleeting copies or representations of other things that are independent of us and don’t change. To that extent, then, reason compels us to contradict or depart from the basic instincts of nature, and to adopt a new set of views about the evidence of our senses."

Hume's Indirect Realism Our basic belief is that the external universe doesn't depend on our perceiving it and would have existed if there had never been anything perceiving it, and that the images our senses present are the external objects they perceive. The slightest philosophy destroys this as it teaches us that images or sensations are the only things that are ever present to our mind (as we move away from a table it gets smaller but the real table exists and doesn't change in size)

Russell's Indirect Realism"Let us give the name of 'sense-data' to the things that are immediately known in sensation: such things as colours, sounds, smells, hardnesses, roughnesses, and so on. We shall give the name 'sensation' to the experience of being immediately aware of these things. Thus, whenever we see a colour, we have a sensation of the colour, but the colour itself is a sense-datum, not a sensation. The colour is that of which we are immediately aware, and the awareness itself is the sensation. It is plain that if we are to know anything about the table, it must be by means of the sense-data--brown colour, oblong shape, smoothness, etc. – which we associate with the table; but, for the reasons which have been given, we cannot say that the table is the sense-data, or even that the sense-data are directly properties of the table. Thus a problem arises as to the relation of the sense-data to the real table, supposing there is such a thing."