What is the attentive process, psychologically considered?  Attention to an object is what takes place whenever that object most completely occupies the mind.  For simplicity’s sake suppose the object be an object of sensation,—­a figure approaching us at a distance on the road.  It is far off, barely perceptible, and hardly moving:  we do not know with certainty whether it is a man or not.  Such an object as this, if carelessly looked at, may hardly catch our attention at all.  The optical impression may affect solely the marginal consciousness, while the mental focus keeps engaged with rival things.  We may indeed not ‘see’ it till some one points it out.  But, if so, how does he point it out?  By his finger, and by describing its appearance,—­by creating a premonitory image of where to look and of what to expect to see.  This premonitory image is already an excitement of the same nerve-centres that are to be concerned with the impression.  The impression comes, and excites them still further; and now the object enters the focus of the field, consciousness being sustained both by impression and by preliminary idea.  But the maximum of attention to it is not yet reached.  Although we see it, we may not care for it; it may suggest nothing important to us; and a rival stream of objects or of thoughts may quickly take our mind away.  If, however, our companion defines it in a significant way, arouses in the mind a set of experiences to be apprehended from it,—­names it an enemy or as a messenger of important tidings,—­the residual and marginal ideas now aroused, so far from being its rivals, become its associates and allies.  They shoot together into one system with it; they converge upon it; they keep it steadily in focus; the mind attends to it with maximum power.

The attentive process, therefore, at its maximum may be physiologically symbolized by a brain-cell played on in two ways, from without and from within.  Incoming currents from the periphery arouse it, and collateral currents from the centres of memory and imagination re-enforce these.

In this process the incoming impression is the newer element; the ideas which re-enforce and sustain it are among the older possessions of the mind.  And the maximum of attention may then be said to be found whenever we have a systematic harmony or unification between the novel and the old.  It is an odd circumstance that neither the old nor the new, by itself, is interesting:  the absolutely old is insipid; the absolutely new makes no appeal at all.  The old in the new is what claims the attention,—­the old with a slightly new turn.  No one wants to hear a lecture on a subject completely disconnected with his previous knowledge, but we all like lectures on subjects of which we know a little already, just as, in the fashions, every year must bring its slight modification of last year’s suit, but an abrupt jump from the fashion of one decade into another would be distasteful to the eye.