Humanity needs practical men, who get the most out of their work, and, without forgetting the general good, safeguard their own interests. But humanity also needs dreamers, for whom the disinterested development of an enterprise is so captivating that it becomes impossible for them to devote their care to their own material profit. A well-organized society should assure to such workers the efficient means of accomplishing their task, in a life freed from material care and freely consecrated to research.