If the madness reaches a high degree, there is complete absence of memory, so that the madman is quite incapable of any reference to what is absent or past, and is only determined by the caprice of the moment in connection with the fictions which, in his mind, fill the past.
 Arthur Schopenhauer, The World as Will and Representation (1819). copy citation

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Author Arthur Schopenhauer
Source The World as Will and Representation
Topic madness memory
Date 1819
Language English
Reference
Note Translated by R. B. Haldane and J. Kemp
Weblink http://www.gutenberg.org/files/38427/38427-h/38427-h.html

Context

“they therefore regard themselves and others as identical with persons who exist only in their imaginary past; they do not recognise some of their acquaintances at all, and thus while they perceive correctly what is actually present, they have only false conceptions of its relations to what is absent. If the madness reaches a high degree, there is complete absence of memory, so that the madman is quite incapable of any reference to what is absent or past, and is only determined by the caprice of the moment in connection with the fictions which, in his mind, fill the past. In such a case, we are never for a moment safe from violence or murder, unless we constantly make the madman aware of the presence of superior force. The knowledge of the madman has this in common with that of the brute, both are confined to the present.” source