Deep-kindled, shews across that sudden blaze
The object of his rapture, vast of size,
With fiercer colours and a night of shade.”[132]
The species of desire which we are considering, however, is not of this fierce and tempestuous kind.
Emotions of a calmer species have the vivifying effect, without the indistinctness; and precisely of this degree is that desire which constitutes attention as coexisting with the sensations, or other feelings to which we are said to attend.
We have found, then, in the desire which accompanies attention, or rather which chiefly constitutes it, the cause of that increased intensity which we sought.
When all the various objects of a scene are of themselves equally, or nearly equally, interesting or indifferent to us, the union of desire, with any particular perception of the group, might be supposed, a priori, to render this perception in some degree more vivid than it was before. It is not necessary that this difference of vividness should take place wholly, or even be very striking, in the first instant; for, by becoming in the first instant even slightly more vivid, it acquires additional colouring and prominence, so as to increase that interest, which led us originally to select it for our first minute observation, and thus to brighten it more and more progressively. Indeed, when we reflect on our consciousness during what is called an effort of attention, we feel that some such progress as this really takes place, the object becoming gradually more distinct while we gaze, till at length it requires a sort of effort to turn away to the other coexisting objects, and to renew with them the same process.
Attention, then, is not a simple mental state, but a process, or a combination of feelings. It is not the result of any peculiar power of the mind, but of those mere laws of perception, by which the increased vividness of one sensation produces a corresponding faintness of others coexisting with it, and of that law of our emotions, by which they communicate greater intensity to every perception, or other feeling, with which they coexist and harmonize.
Footnotes
[131] Thomson's Seasons—Spring, v. 1006–1021.