But for anybody who thinks great art and great philosophy have nothing to do with commerce, let him visit Athens and Baghdad to ask how Aristotle and al-Khwarizmi had the leisure time to philosophise. Let him visit Florence, Pisa and Venice and inquire into how Michelangelo, Galileo and Vivaldi were paid. Let him go to Amsterdam and London and ask what funded Spinoza, Rembrandt, Newton and Darwin.
