Lectures on the Philosophy of the Human Mind (Vol. 1 of 3)

by Thomas Brown

The comprehensive knowledge thus acquired, we owe to the mere skill with which we have directed our eyes from object to object. The knowledge has been acquired in parts successively; but, when acquired, it is present at once to our mind, in the same manner, as the objects which it retraces to us, are all present to the single glance of the eye that beholds them.

The description which I have now given you, very nearly after the words of Condillac, is, I think, a very faithful representation of a process of which we must all repeatedly have been conscious. It seems to me however, faithful as it is, as a mere description, to leave the great difficulty unexplained, and even unremarked. We see a multitude of objects, and we have one complex indistinct feeling. We wish to know the scene more accurately, and in consequence of this wish, though the objects themselves continue as before, we no longer seem to view them all, but only one, or a few; and the few, which we now see, we see more distinctly. Such I conceive to be the process; but the difference is, that though we seem to view only a few objects, and these much more distinctly, the field of the eye still comprehends a wide expanse, the light from which scarcely affects us, while the light from other parts of it, though not more brilliant, produces in us distinct perception. It is vain for Condillac to say, that it is in consequence of a faculty which we have of directing our eyes on one subject, a faculty which is the result of our organization, and which is common to all mankind; for, in the first place, if this direction of our eyes, of which he speaks, on a single object, be meant, in its strict sense, of the eye itself, which we direct, it is not true that we have any such faculty. We cannot direct our eyes so as not to comprehend equally in our field of vision, many objects beside that single object which is supposed to have fixed our attention; and if, by the direction of our eyes, be meant the exclusive or limited perception by our mind itself, there remains the difficulty,—how it happens, that while light from innumerable objects falls on our retina as before, it no longer produces any distinct vision relatively to the objects from which it comes,—while light certainly not more brilliant, from other objects, produces vision much more distinct than before. Let us consider this difficulty which, in truth, constitutes the principal phenomenon of attention, a little more fully.

When Condillac speaks of the faculty of the mind, by which he supposes it capable of directing the eye, exclusively, on certain objects, he must speak of that only, of which we are conscious, previously to the more distinct perception of those objects, as certain parts of the scene.

What is it, then, of which we are conscious, between the indistinct perception of the wide scene, and the distinct perception of parts of the scene?

In the first place, there is a general desire of knowing the scene more accurately. This is the primary feeling of the process of attention. But this primary feeling is soon succeeded by others. Indistinct as the whole complex scene may be, some parts of it more brilliant, or more striking in general character, are less indistinct than others. There are a few more prominent parts, as Condillac says, around which the rest are indistinctly arranged.

With some one of these, then, as in itself more impressive and attractive, we begin; our general desire of knowing the whole scene having been followed by a wish to know this principal part more accurately.

The next step is to prevent the eye itself from wandering, that no new objects may distract it, and that there may be as little confusion as possible of the rays from different objects, on that part of the retina, on which the rays fell from the particular object which we wish to consider. We fix our eyes, therefore, and our whole body, as steadily as we can, by the muscles subservient to these purposes.

So far, unquestionably, no new faculty is exercised. We have merely the desire of knowing the scene before us,—the selection of some prominent object, or rather the mere perception of it, as peculiarly prominent,—the desire of knowing it particularly,—and the contraction of a few muscles, in obedience to our volition.

No sooner, however, has all this taken place, than instantly, or almost instantly, and without our consciousness of any new and peculiar state of mind intervening in the process, the landscape becomes to our vision altogether different. Certain parts only, those parts which we wished to know particularly, are seen by us; the remaining parts seem almost to have vanished. It is as if every thing before had been but the doubtful colouring of enchantment, which had disappeared, and left to us the few prominent realities on which we gaze; or rather, it is as if some instant enchantment, obedient to our wishes, had dissolved every reality besides, and brought closer to our sight the few objects which we desired to see.

Still, however, all of which we are truly conscious, as preceding immediately the change of appearance in the scene, is the mere desire, of which I have spoken, combined certainly with expectation of that more distinct vision which follows. There may be a combination of feelings, but no new and peculiar feeling, either as simple, or coexisting with other feelings,—no indication, in short, of the exercise of new power.