Voltaire was not merely one of those ‘paper philosophers,’ whose intrusion into the fields of physical science its professional followers are justly wont to resent. He was an active experimenter, and more than one letter remains, containing instructions to his agent in Paris to forward him retorts, air-pumps, and other instruments, with the wise hint in one place, a hint by no means of a miser, ‘In the matter of buying things, my friend, you should always prefer the good and sound even if a little dear, to what is only middling but cheaper[92].’ His correspondence for some years proves the diligence and sincerity of his interest in science. Yet it is tolerably clear that the man who did so much to familiarise France with the most illustrious of physicists, was himself devoid of true scientific aptitude. After long and persevering labour in this region, Voltaire consulted Clairaut on the progress he had made. The latter, with a loyal frankness which Voltaire knew how to appreciate, answered that even with the most stubborn labour he was not likely to attain to anything beyond mediocrity in science, and that he would be only throwing away time which he owed to poetry and philosophy.[93] The advice was taken; for, as we have already said, Voltaire’s self-love was never fatuous, and the independent search of physical truth was given up. There is plainly no reason to regret the pains which Voltaire took in this kind of inquiry, not because the study of the sciences extends the range of poetic study and enriches verse with fresh images, but because the number of sorts of knowledge in which a man feels at home and is intelligently cognisant of their scope and issues, even if he be wholly incompetent to assist in the progress of discovery, increases that intellectual confidence and self-respect of understanding, which so fortifies and stimulates him in his own special order of work. We cannot precisely contend that this encyclopædic quality is an indispensable condition of such self-respect in every kind of temper. It certainly was so with Voltaire. ‘After all, my dear friend,’ he wrote to Cideville, ‘it is right to give every possible form to our soul. It is a flame that God has intrusted to us, we are bound to feed it with all that we find most precious. We should introduce into our existence all imaginable modes, and open every door of the soul to all sorts of knowledge and all sorts of feelings. So long as it does not all go in pell-mell there is plenty of room for everything.[94]