Famous quotes containing the words stimulus and/or material:
“Decisive inventions and discoveries always are initiated by an intellectual or moral stimulus as their actual motivating force, but, usually, the final impetus to human action is given by material impulses ... merchants stood as a driving force behind the heroes of the age of discovery; this first heroic impulse to conquer the world emanated from very mortal forces—in the beginning, there was spice.”
—Stefan Zweig (18811942)
“We soon saw, as he saw, that he was not to be pardoned or rescued by men. That would have been to disarm him, to restore to him a material weapon, a Sharp’s rifle, when he had taken up the sword of the spirit,—the sword with which he has really won his greatest and most memorable victories. Now he has not laid aside the sword of the spirit, for he is pure spirit himself, and his sword is pure spirit also.”
—Henry David Thoreau (1817–1862)