5. Baron d'Holbach had a more powerful brain than Helvetius, but his writings had probably less influence, though he was the spiritual father of two prominent Revolutionaries, Hebert and Chaumette. His System of Nature (1770) develops a purely naturalistic theory of the universe, in which the prevalent Deism is rejected: there is no God; material Nature stands out alone, self-sufficing, dominis privata superbis. The book suggests how the Lucretian theory of development might have led to the idea of Progress. But it sent a chilly shock to the hearts of many and probably convinced few. The effective part was the outspoken and passionate indictment of governments and religions as causes of most of the miseries of mankind. It is in other works, especially in his Social System, that his views of Progress are to be sought. Man is simply a part of nature; he has no privileged position, and he is born neither good nor bad. Erras, as Seneca said, si existumas vitia nobiscum esse: supervenerunt, ingesta sunt. [Footnote: Seneca, Ep. 124.] We are made good or bad by education, public opinion, laws, government; and here the author points to the significance of the instinct of imitation as a social force, which a modern writer, M. Tarde, has worked into a system. The evils, which are due to the errors of tyranny and superstition, the force of truth will gradually diminish if it cannot completely banish them; for our governments and laws may be perfected by the progress of useful knowledge. But the process will be a long one: centuries of continuous mental effort in unravelling the causes of social ill-being and repeated experiments to determine the remedies (des experiences reiterees de la societe). In any case we cannot look forward to the attainment of an unchangeable or unqualified felicity. That is a mere chimera "incompatible with the nature of a being whose feeble machine is subject to derangement and whose ardent imagination will not always submit to the guidance of reason. Sometimes to enjoy, sometimes to suffer, is the lot of man; to enjoy more often than to suffer is what constitutes well-being." D'Holbach was a strict determinist; he left no room for freewill in the rigorous succession of cause and effect, and the pages in which he drives home the theory of causal necessity are still worth reading. From his naturalistic principles he inferred that the distinction between nature and art is not fundamental; civilisation is as rational as the savage state. Here he was at one with Aristotle.