Some choice bits from Chapter 3, “The Composition of Music” from his Poetics of Music in the form of six lessons“, which befuddled me in college but now makes sense.
All creation presupposes at its origin a sort of appetite that is brought on by the foretaste of discovery. This foretaste of the creative act accompanies the intuitive grasp of an unknown entity already possessed but not yet intelligible, an entity that will not take definite shape except by the action of a constantly vigilant technique.
This appetite that is aroused in me at the mere thought of putting in order musical elements that have attracted my attention is not at all a fortuitous thing like inspiration, but as habitual and periodic, if not as constant, as a natural need.
The premonition of an obligation, this foretaste of a pleasure, this conditioned reflex, as a modern physiologist would say, shows clearly that the idea of discovery and hard work is what attracts me.
The very act of putting my work on paper, of, as we say kneading the dough, is for me inseparable from the pleasure of creation. So far as I am concerned, I cannot separate the spiritual effort from the psychological and physical effort; they confront me on the same level and do not present a hierarchy. The word artist which, as it is most generally understood today, bestows on its bearer the highest intellectual prestige, the privilege of being accepted as a pure mind–this pretentious term is in my view entirely incompatible with the role of homo faber.
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We have a duty toward music, namely to invent it. I recall once during the war when I was crossing the French border, a gendarme asked me what my profession was. I told him quite naturally that I was an inventor of music. The gendarme, then verifying my passport, asked me why I was listed as a composer. I told him that the expression “inventor of music” seems to fit my profession more exactly than the term applied to me in the documents authorizing me to cross borders.
Invention presupposes imagination but should not be confused with it. For the act of invention implies the necessity of a lucky find and of achieving full realization of this find. What we imagine does not necessarily take on a concrete form and may remain in the state of virtuality, whereas invention is not conceivable apart from actual working out…
A Few Reasonable Words 