To commit the least possible sin is the law for man. To live without sin is the dream of an angel. Everything terrestrial is subject to sin. Sin is a gravitation.
One might think that the money value of an invention constitutes its reward to the man who loves his work. But speaking for myself, I can honestly say this is not so... I continue to find my greatest pleasure, and so my reward, in the work that precedes what the world calls success.