ce distinguished certain kinds of unreasoned or
uninferred knowledge. Of these the two best known are perception and
memory. When I see an object before me, or when I recall an event in my
past experience, I am supposed to grasp a piece of knowledge directly,
to know something immediately, and not through the medium of something
else. Yet I know differently in the two cases. In the first I know by
what is called a presentative process, namely, that of sense-perception;
in the second I know by a representative process, namely, that of
reproduction, or on the evidence of memory. In the one case the object
of cognition is present to my perceptive faculties; in the other it is
recalled by the power of memory.

Scientific psychology tends, no doubt, to break down some of these
popular distinctions. Just as the zoologist sometimes groups together
varieties of animals which the unscientific eye would never think of
connecting, so the psychologist may analyze mental operations which
appear widely dissimilar to the popular mind, and reduce them to one
fundamental process. Thus recent psychology draws no sharp distinction
between perception and recollection. It finds in both very much the same
elements, though combined in a different way. Strictly speaking, indeed,
perception must be defined as a presentative-representative operation.
To the psychologist it comes to very much the same thing whether, for
example, on a visit to Switzerland, our minds are occupied in
_perceiving_ the distance of a mountain or in _remembering_ some
pleasant excursion which we made to it on a former visit. In both cases
there is a reinstatement of the past, a reproduction of earlier
experience, a process of adding to a present impression a product of
imagination--taking this word in its widest sense. In both cases the
same laws of reproduction or association are illustrated.

Just as a deep and exhaustive analysis of the intellectual operations
thus tends to identify their various forms as they are distinguished by
the popular mind, so a thorough investigation of the flaws in these
operations, that is to say, the counterfeits of knowledge, will probably
lead to an identification of the essential mental process which
underlies them. It is apparent, for example, that, whether a man
_projects_ some figment of his imagination into the external world,
giving it, present material reality, or whether (if I may be allowed the
term) he _retrojects_ it into th