On “direct” vs “indirect” perception, JL Austin makes some great points regarding the language of the debate in his manuscripts
. The use of these terms in my own and in other’s arguments admittedly sent us off in wild directions. I’m going to quote them here.
1. First of all, it is essential to realize that here the notion of perceiving indirectly wears the trousers—'directly' takes whatever sense it has from the contrast with its opposite while 'indirectly' itself(a) has a use only in special cases, and also (b) has different uses in different cases—though that doesn't mean, of course, that there is not a good reason why we should use the same word. We might, for example, contrast the man who saw the procession directly with the man who saw it through a periscope; or we might contrast the place from which you can watch the door directly with the place from which you can see it only in the mirror. Perhaps we might contrast seeing you directly with seeing, say, your shadow on the blind; and perhaps we might contrast hearing the music directly with hearing it relayed outside the concert hall. However, these last two cases suggest two further points.
2. The 'first of these points is that the notion of not perceiving 'directly' seems most at home where, as with the periscope and the mirror, it retains its link with the notion of kink in direction. It seems that we must not be looking straight at the object in question. For this reason seeing your shadow on the blind is a doubtful case; and seeing you, for instance, through binoculars or spectacles is certainly not a case of seeing you indirectly at all. For such cases as these last we have quite distinct contrasts and different expressions-'with the naked eye' as opposed to 'with a telescope', 'with unaided vision' as opposed to 'with glasses on'. (These expressions, in fact, are much more firmly established in ordinary use than 'directly' is.)
3. And the other point is that, partly no doubt for the above reason, the notion of indirect perception is not naturally at home with senses other than sight. With the other senses there is nothing quite analogous with the 'line of vision'. The most natural sense of 'hearing indirectly', of course, is that of being told something by an intermediary—a quite different matter. But do I hear a shout indirectly, when I hear the echo? If I touch you with a barge-pole, do I touch you indirectly? Or if you offer me a pig in a poke, might I feel the pig indirectly—through the poke? And what smelling indirectly might be I have simply no idea. For this reason alone there seems to be something badly wrong with the question, 'Do we perceive things directly or not?', where perceiving is evidently intended to cover the employment of any of the senses.
4. But it is, of course, for other reasons too extremely doubtful how far the notion of perceiving indirectly could or should be extended. Does it, or should it, cover the telephone, for instance? Or television? Or radar? Have we moved too far in these cases from the original metaphor They at any rate satisfy what seems to be a necessary condition—namely, concurrent existence and concomitant variation as between what is perceived in the straightforward way (the sounds in the receiver, the picture and the blips on the screen) and the candidate for what we might be prepared to describe as being perceived indirectly. And this condition fairly clearly rules out as cases of indirect perception seeing photographs (which statically record scenes from the past) and seeing films (which, though not static, are not seen contemporaneously with the events thus recorded). Certainly, there is a line to be drawn somewhere. It is certain, for instance, that we should not be prepared to speak of indirect perception in every case in which we see something from which the existence (or occurrence) of something else can be inferred; we should not say we see the guns indirectly, if we see in the distance only the flashes of guns.
5· Rather differently, if we are to be seriously inclined to speak of something as being perceived indirectly, it seems that it has to be the kind of thing which we (sometimes at least) just perceive, or could perceive, or which—like the backs of our own heads—others could perceive. For otherwise we don't want to say that we perceive the thing at all, even indirectly. No doubt there are complications here (raised, perhaps, by the electron microscope, for example, about which I know little or nothing). But it seems clear that, in general, we should want to distinguish between seeing indirectly, e.g. in a mirror, what we might have just seen, and seeing signs (or effects), e.g. in a Wilson cloud-chamber, of something not itself perceptible at all. It would at least not come naturally to speak of the latter as a case of perceiving something indirectly.
6. And one final point. For reasons not very obscure, we always prefer in practice what might be called the cash-value expression to the 'indirect' metaphor. If I were to report that I see enemy ships indirectly, I should merely provoke the question what exactly I mean.'I mean that I can see these blips on the radar screen'-'Well, why didn't you say so then?' (Compare 'I can see an unreal duck.'-'What on earth do you mean?' 'It's a decoy duck'-'Ah, I see. Why didn't you say so at once?') That is, there is seldom if ever any particular point in actually saying 'indirectly' (or 'unreal'); the expression can cover too many rather different cases to be just what is wanted in any particular case.
Thus, it is quite plain that the philosophers' use of 'directly perceive', whatever it may be, is not the ordinary, or any familiar, use; for in that use it is not only false but simply absurd to say that such objects as pens or cigarettes are never perceived directly. But we are given no explanation or definition of this new use—on the contrary, it is glibly trotted out as if we were all quite familiar with it already. It is clear, too, that the philosophers' use, whatever it may be, offends against several of the canons just mentioned above-no restrictions whatever seem to be envisaged to any special circumstances or to any of the senses in particular, and moreover it seems that what we are to be said to perceive indirectly is never—is not the kind of thing which ever could be—perceived directly.