But, as we have said, the greater part of the sense impressions stored away in our memories are those previously received through the senses of sight and hearing, respectively. The majority of sense impressions, stored away in the memory, have been received more or less involuntarily, that is with the application of but a slight degree of attention. They are more or less indistinct and hazy, and are recalled with difficulty, the remembrance of them generally coming about without conscious effort, according to the law of association. That is, they come principally when we are thinking about something else upon which we have given thought and attention, and with which they have been associated. There is quite a difference between the remembrance of sense impressions received in this way, and those which we record by the bestowal of attention, interest and concentration.

The sense impressions of sight are by far the most numerous in our subconscious storehouse. We are constantly exercising our sense of sight, and receiving thousands of different sight impressions every hour. But the majority of these impressions are but faintly recorded upon the memory, because we give to them but little attention or interest But it is astonishing, at times, when we find that when we recall some important event or incident we also recall many faint sight impressions of which we did not dream we had any record. To realize the important part played by sight impressions in the phenomena of memory, recall some particular time or event in your life, and see how many more things that you saw are remembered, compared with the number of things that you heard, or tasted, or felt or smelled.