We are, however, immediately encountered by the question. If the mind cannot will an Idea, what power does it possess of introducing any idea into a train, but such as comes of its own accord? If it has the idea, it is in the train already. If it has it not, what can it do in order to obtain it? There is the existing train; but how can that be made any thing but what it is; or have any associations but those which are already established?

In cases where language is too imperfect to ensure the conveyance of definite ideas, there is an advantage in particular instances. There are two familiar processes, which are commonly adduced as examples of the power which the mind exercises over its trains. The one is, the endeavour to recollect something we do not remember. The other is, the process of attention.

When anything is remembered, the idea of the thing is always in the mind along with certain associations. In recollection, therefore, the object is attained by the excitement of this idea. Sometimes the effort which we make is successful; sometimes it is not. We are said to will to recollect; but this is obviously an improper expression. To recollect is to call up an Idea. But this, as we have seen already, is not within the province of will. When it is said 361 that we will to recollect, the meaning only is, that we desire to recollect.

But it is also to be inquired, what here is the meaning of the word Desire. We have seen that it is a term applied to Pleasure, or the Cause of Pleasure. The idea, in this instance, which the mind is in quest of, is desired. But why desired? As Pleasure; or the Cause of Pleasure? As Cause, we may reply, in all instances. The idea is wanted for some purpose or end. In that End the pleasure is involved.

The End is thus a pleasurable, that is, an interesting, Idea. But it is in the character of interesting ideas, to dwell in the mind. The meaning is, that they are easily called up by other ideas; and, thus, that there is a perpetual recurrence of them. A young man in love, is said to be engrossed with the idea of his mistress. No sooner has her idea suggested another idea, that is, given place to it, than her idea is again suggested by another, and so on, continually. The man, who is to be executed to-morrow, can think of nothing but the terrible event which is approaching. It can be banished, hardly for an instant. Every thing serves to recall it: and along with it a rush of ideas of the most painful description. There is no law of association more remarkable than that of the rapidity with which pleasurable and painful ideas call up trains of great complexity, and the facility with which they themselves are excited by almost every idea which enters the mind.

When we endeavour, therefore, to recollect any thing, the pleasurable idea, the purpose or end, predominates in the mind, and gives birth to those 362 associations, which are called the effort of recollection. The idea sought after, is sought as a means to this end. Till that idea is recalled, the Idea of the end, that is, an unsatisfied desire, exists, and calls up one circumstance after another, more or less connected with the Idea which is sought after. If these circumstances do not recall the idea; the feeling of unsatisfied desire still continues. The feeling of unsatisfied desire, accompanying successive cases of association, constitutes the feeling to which we give the name of effort of recollection. And the Idea of the End, perpetually calling up the idea of the absence of what is wanted, as the means to that end, and hence calling up in close association every circumstance connected with that unknown something, constitutes the feeling which we call casting about, for the unknown Idea. I believe that this is a full, though summary account of the mental process, or succession of ideas, which takes place when we endeavour to recall a forgotten idea.

The other process, through which the mind is supposed to influence its trains, is Attention. We seem to have the power of attending, or not attending to any object; by which is meant, that we can Will to attend to it, or not to attend. By attending to an object, we give it the opportunity of exciting all the ideas with which it is associated. By not attending to it we deprive it of more or less of that opportunity. And if the will has this power over every idea in a train, it has thence a power, which may be called unlimited, over the train.

What remains, therefore, to complete this inquiry, is, to point out the real process, on which the name 363 ATTENTION is in this manner bestowed. The exposition has been substantially given by preceding writers. But it is desirable, if it be in our power, to set forth the several steps of the process a little more distinctly than has hitherto been done.

At first sight, the objects of attention seem to be infinite. When traced to their sources, however, it is found, that they are of two species only. We attend to Sensations; we attend to Ideas; and there is no other object of our attention.

For the present purpose, it is peculiarly necessary to bear in mind the important distinction we have already noticed, between the class of indifferent sensations, and the class of pleasurable or painful, which we may call, by one name, interesting, sensations. Uninteresting sensations are never, for their own sakes, an object of attention. If ever they become objects of attention, it is when they are considered as causes, or signs, of interesting sensations.