Let moralists say what they will, the human understanding is greatly indebted to the passions, which, on their side, are likewise universally allowed to be greatly indebted to the human understanding. It is by the activity of our passions, that our reason improves: we covet knowledge merely because we covet enjoyment, and it is impossible to conceive why a man exempt from fears and desires should take the trouble to reason. The passions, in their turn, owe their origin to our wants, and their increase to our progress in science; for we cannot desire or fear anything, but in consequence of the ideas we have of it, or of the simple impulses of nature; and savage man, destitute of every species of knowledge, experiences no passions but those of this last kind; his desires never extend beyond his physical wants; he knows no goods but food, a female, and rest; he fears no evil but pain, and hunger; I say pain, and not death; for no animal, merely as such, will ever know what it is to die, and the knowledge of death, and of its terrors, is one of the first acquisitions made by man, in consequence of his deviating from the animal state. I could easily, were it requisite, cite facts in support of this opinion, and show, that the progress of the mind has everywhere kept pace exactly with the wants, to which nature had left the inhabitants exposed, or to which circumstances had subjected them, and consequently to the passions, which inclined them to provide for these wants. I could exhibit in Egypt the arts starting up, and extending themselves with the inundations of the Nile; I could pursue them in their progress among the Greeks, where they were seen to bud forth, grow, and rise to the heavens, in the midst of the sands and rocks of Attica, without being able to take root on the fertile banks of the Eurotas; I would observe that, in general, the inhabitants of the north are more industrious than those of the south, because they can less do without industry; as if nature thus meant to make all things equal, by giving to the mind that fertility she has denied to the soil.