When there is no unerring objective record to be found, we may have recourse to the less satisfactory method of comparing our recollections with those of others.

By so doing we may reach a rough average recollection which shall at least be free from any individual error corresponding to that of personal equation in perception.

But even thus we cannot be sure of eliminating all error, since there may be a cause of illusion acting on all our minds alike, as, for example, the extraordinary nature of the occurrence, which would pretty certainly lead to a common exaggeration of its magnitude, etc., and since, moreover, this process of comparing recollections affords an opportunity for that reading back a present preconception into the past to which reference has already been made.
The result of our inquiry is less alarming than it looks at first sight.
Knowledge is valuable for action, and error is chiefly hurtful in so far as it misdirects conduct.

Now, in a general way, we do not need to act upon a recollection of single remote events; our conduct is sufficiently shaped by an accurate recollection of single recent events, together with those bundles of recollections of recurring events and sequences of events which constitute our knowledge of ourselves and our common knowledge of the world about us.

Nature has done commendably well in endowing us with the means of cultivating our memories up to this point, and we ought not to blame her for not giving us powers which would only very rarely prove of any appreciable practical service to us.
NOTE.
MOMENTARY ILLUSIONS OF SELF-CONSCIOUSNESS.
The account of the apparent ruptures in our personal identity given in this chapter may help us to understand the strange tendency to confuse self with other objects which occasionally appears in waking consciousness and in dreams.