it. We suffer equal pain from the pertinacious adhesion of unwelcome images, as from the evanescence of those which are pleasing and useful; and it may be doubted whether we should be more benefited by the art of memory or the art of forgetfulness.
Forgetfulness is necessary to remembrance. Ideas are retained by renovation of that impression which time is always wearing away, and which new images are striving to obliterate. If useless thoughts could be expelled from the mind, all the valuable parts of our knowledge would more frequently recur, and every recurrence would reinstate them in their former place.
It is impossible to consider, without some regret, how much might have been learned, or how much might have been invented by a rational and vigorous application of time, uselessly or painfully passed in the revocation of events which have left neither good nor evil behind them, in grief for misfortunes either repaired or irreparable, in resentment of injuries known only to ourselves, of which death has put the authors beyond our power.
Philosophy has accumulated precept upon precept, to warn us against the anticipation of future calamities. All useless misery is certainly folly, and he that feels evils before they
