One often hears it said that genius is nothing but a power of sustained attention, and the popular impression probably prevails that men of genius are remarkable for their voluntary powers in this direction. But a little introspective observation will show any one that voluntary attention cannot be continuously sustained,—­that it comes in beats. When we are studying an uninteresting subject, if our mind tends to wander, we have to bring back our attention every now and then by using distinct pulses of effort, which revivify the topic for a moment, the mind then running on for a certain number of seconds or minutes with spontaneous interest, until again some intercurrent idea captures it and takes it off.  Then the processes of volitional recall must be repeated once more.  Voluntary attention, in short, is only a momentary affair.  The process, whatever it is, exhausts itself in the single act; and, unless the matter is then taken in hand by some trace of interest inherent in the subject, the mind fails to follow it at all.  The sustained attention of the genius, sticking to his subject for hours together, is for the most part of the passive sort.  The minds of geniuses are full of copious and original associations.  The subject of thought, once started, develops all sorts of fascinating consequences.  The attention is led along one of these to another in the most interesting manner, and the attention never once tends to stray away.

In a commonplace mind, on the other hand, a subject develops much less numerous associates:  it dies out then quickly; and, if the man is to keep up thinking of it at all, he must bring his attention back to it by a violent wrench.  In him, therefore, the faculty of voluntary attention receives abundant opportunity for cultivation in daily life.  It is your despised business man, your common man of affairs, (so looked down on by the literary awarders of fame) whose virtue in this regard is likely to be most developed; for he has to listen to the concerns of so many uninteresting people, and to transact so much drudging detail, that the faculty in question is always kept in training.  A genius, on the contrary, is the man in whom you are least likely to find the power of attending to anything insipid or distasteful in itself.  He breaks his engagements, leaves his letters unanswered, neglects his family duties incorrigibly, because he is powerless to turn his attention down and back from those more interesting trains of imagery with which his genius constantly occupies his mind.

Voluntary attention is thus an essentially instantaneous affair.  You can claim it, for your purposes in the schoolroom, by commanding it in loud, imperious tones; and you can easily get it in this way.  But, unless the subject to which you thus recall their attention has inherent power to interest the pupils, you will have got it for only a brief moment; and their minds will soon be wandering again.  To keep them where you have called them, you must make the subject too interesting for them to wander again.  And for that there is one prescription; but the prescription, like all our prescriptions, is abstract, and, to get practical results from it, you must couple it with mother-wit.