Only through [such] pure contemplation … can Ideas be comprehended; and the nature of genius consists in pre-eminent capacity for such contemplation. Now, as this requires that a man* should entirely forget himself and the relations in which he stands, genius is simply the completest objectivity, i.e., the objective tendency of the mind, as opposed to the subjective, which is directed to one’s own self — in other words, to the will. Thus genius is the faculty of continuing in the state of pure perception, of losing oneself in perception, and of enlisting in this service the knowledge which originally existed only for the service of the will; that is to say, genius is the power of leaving one’s own interests, wishes, and aims entirely out of sight, thus of entirely renouncing one’s own personality for a time, so as to remain pure knowing subject, clear vision of the world; and this not merely at moments, but for a sufficient length of time, and with sufficient consciousness, to enable one to reproduce by deliberate art what has thus been apprehended.
Schopenhauer - The World as Will and Representation