To Madame d'Epinay, Naples, 31 August, 1771

 
You, my dear lady, have done me a terrible wrong. I saw that a big package arrived from you; I enjoyed the thought of it in advance; I imagined the longest letter in the world, and instead of finding that you wrote me, I found that you had transcribed a selection from Voltaire to send to me. To avenge myself, I may transcribe a selection from my prayer book to send you. I admit that the bit about curiosity from Voltaire is superb, sublime, new, and true. I admit also that he would be right in everything if he didn't forget that curiosity is a passion, or, if you like, a feeling excited in us once we feel a perfect secuirty and don't occupy ourselves anymore with ourselves: that is the origin of all spectacles... (skipping over some)... it's a feeling particular to man, unique in him, which he has in common with no other animal. Animals don't have quite the same idea. Do in front of a troupe of sheep anything you want; if you don't touch them, they're not interested in you. If animals give some sign of curiosity, it's because they are frightened, and nothing else. One can frighten animals, one cannot make them curious. However, according to what I said, fear is opposed to curiosity. If curiosity is impossible for animals, a curious human being is therefore more of a human being than a non-curious one: and this is in fact true. Newton was so curious that he looked for the cause of the movement of the moon, the sea, etc.. The most curious people therefore are more human than other people. That is the most beautiful praise that has ever been made of the idlers in Paris. This idea is profound, and I haven't the time to detail it to you. Without a doubt, Voltaire didn't have to write as fast in his article on curiosity. He wrote better, because he knows his language; but if you want to take the pains to develop what I've scrawled, you will find a great piece of the human heart; man, the curious animal; man, susceptible to spectacles. Nearly all the sciences are only curiosities, and the key to everything is a base of safety and a situation without suffering in the curious animal... (skipping over a few sentences where he asks her to say hello to friends)... Good night, I am short on time. I embrace you.