There is a vivid illustration of this unexpected business-like quality in Diderot, in a conversation that he once had with D'Alembert. The dialogue is interesting to those who happen to be curious as to the characters of two famous men. It was in 1759, when D'Alembert was tired of the Encyclopædia, and was for making hard terms as the condition of his return to it. "If," said Diderot to him, "six months ago, when we met to deliberate on the continuation of the work, you had then proposed these terms, the booksellers would have closed with them on the spot, but now, when they have the strongest reasons to be out of humour with you, that is another thing."
"And pray, what reasons?"
"Can you ask me?"
"Certainly."
"Then I will tell you. You have a bargain with the booksellers; the terms are stipulated; you have nothing to ask beyond them. If you worked harder than you were bound to do, that was out of your interest in the book, out of friendship to me, out of respect for yourself; people do not pay in money for such motives as these. Still they sent you twenty louis a volume: that makes a hundred and forty louis that you had beyond what was due to you. You plan a journey to Wesel [in 1752, to meet Frederick of Prussia] at a time when you were wanted by them here; they do not detain you; on the contrary, you are short of money, and they supply you. You accept a couple of hundred louis; this debt you forget for two or three years. At the end of that rather long term you bethink you of paying. What do they do? They hand you back your note of hand torn up, with all the air of being very glad to have served you. Then, after all, you turn your back on an undertaking in which they have embarked their whole fortunes: an affair of a couple of millions is a trifle unworthy of the attention of a philosopher like you.... But that is not all. You have a fancy for collecting together different pieces scattered through the Encyclopædia; nothing can be more opposed to their interests; they put this to you, you insist, the edition is produced, they advance the cost, you share the profits. It seemed that, after having thus twice paid you for their work, they had a right to look upon it as theirs. Yet you go in search of a bookseller in some quite different direction, and sell him in a mass what does not belong to you."
"They gave me a thousand grounds for dissatisfaction."
"Quelle défaite! There are no small things between friends. Everything weighs, because friendship is a commerce of purity and delicacy; but are the booksellers your friends? Then your behaviour to them is horrible. If not, then you have nothing to say against them. If the public were called upon to judge between you and them, my friend, you would be covered with shame."
"What, can it be you, Diderot, who thus take the side of the booksellers?"
"My grievances against them do not prevent me from seeing their grievances against you. After all this show of pride, confess now that you are cutting a very sorry figure?"[243]
All this was the language of good sense, and there is no evidence that Diderot ever swerved from that fair and honourable attitude in his own dealings with the booksellers. Yet he was able to treat them with a sturdy spirit when they forgot themselves. Panckoucke, one of the great publishers of the time, came to him one day. "He was swollen with the arrogance of a parvenu, and thinking apparently that he could use me like one of those poor devils who depend upon him for a crust of bread, he permitted himself to fly into a passion; but it did not succeed at all. I let him go on as he pleased; then I got up abruptly, I took him by the arm, and I said to him: 'M. Panckoucke, in whatever place it may be, in the street, in church, in a bad house, and to whomsoever it may be, it is always right to keep a civil tongue in one's head. But that is all the more necessary still, when you speak to a man who has as little patience as I have, and that, too, in his own house. Go to the devil, you and your work. If you would give me twenty thousand louis, and I could do your business for you in the twinkling of an eye, I would not stir a finger. Be kind enough to be off."[244]