When at last during the first half of the eighteenth century, Europe experienced a tremendous outbreak of intellectual curiosity, the purveyors of encyclopedias entered into a veritable Paradise. Such books, then as now, were usually compiled by very poor scholars who could live on eight dollars a week and whose personal services counted for less than the money spent upon paper and ink. England especially was a great country for this sort of literature and so it was quite natural that John Mills, a Britisher who lived in Paris, should think of translating the successful “Universal Dictionary” of Ephraim Chambers into the French language that he might peddle his product among the subjects of good King Louis and grow rich. For this purpose he associated himself with a German professor and then approached Lebreton, the king’s printer, to do the actual publishing. To make a long story short, Lebreton, who saw a chance to make a small fortune, deliberately swindled his partner and as soon as he had frozen Mills and the Teuton doctor out of the enterprise, continued to publish the pirated edition on his own account. He called the forthcoming work the “Encyclopédie ou Dictionnaire Universel des Arts et des Sciences” and issued a series of beautiful prospectuses with such a tremendous selling appeal that the list of subscribers was soon filled.

Then he hired himself a professor of philosophy in the Collège de France to act as his editor-in-chief, bought a lot of paper and awaited results.

Unfortunately, the work of writing an encyclopedia did not prove as simple as Lebreton had thought. The professor produced notes but no articles, the subscribers loudly clamored for Volume I and everything was in great disorder.

In this emergency Lebreton remembered that a “Universal Dictionary of Medicine” which had appeared only a few months before had been very favorably received. He sent for the editor of this medical handbook and hired him on the spot. And so it happened that a mere encyclopedia became the “Encyclopédie.” For the new editor was no one less than Denis Diderot and the work which was to have been a hack job became one of the most important contributions of the eighteenth century towards the sum total of human enlightenment.

Diderot at that time was thirty-seven years old and his life had been neither easy nor happy. He had refused to do what all respectable young Frenchmen were supposed to do and go to a university. Instead, as soon as he could get away from his Jesuit teachers, he had proceeded to Paris to become a man of letters. After a short period of starvation (acting upon the principle that two can go hungry just as cheaply as one) he had married a lady who proved to be a terribly pious woman and an uncompromising shrew, a combination which is by no means as rare as some people seem to believe. But as he was obliged to support her, he had been forced to take all sorts of odd jobs and to compile all sorts of books from “Inquiries concerning Virtue and Merit” to a rather disreputable rehash of Boccaccio’s “Decameron.” In his heart, however, this pupil of Bayle remained faithful to his liberal ideals. Soon the government (after the fashion of governments during times of stress) discovered that this inoffensive looking young author maintained grave doubts about the story of creation as rendered in the first chapter of Genesis and otherwise was considerable of a heretic. In consequence whereof Diderot was conducted to the prison of Vincennes and there held under lock and key for almost three months.

It was after his release from jail that he entered the service of Lebreton. Diderot was one of the most eloquent men of his time. He saw the chance of a lifetime in the enterprise of which he was to be the head. A mere rehash of Chambers’ old material seemed entirely beneath his dignity. It was an era of tremendous mental activity. Very well! Let the Encyclopedia of Lebreton contain the latest word upon every conceivable subject and let the articles be written by the foremost authorities in every line of human endeavor.

Diderot was so full of enthusiasm that he actually persuaded Lebreton to give him full command and unlimited time. Then he made up a tentative list of his coöperators, took a large sheet of foolscap and began, “A: the first letter of the alphabet, etc., etc.”

Twenty years later he reached the Z and the job was done. Rarely, however, has a man worked under such tremendous disadvantages. Lebreton had increased his original capital when he hired Diderot, but he never paid his editor more than five hundred dollars per year. And as for the other people who were supposed to lend their assistance, well, we all know how those things are. They were either busy just then, or they would do it next month, or they had to go to the country to see their grandmother. With the result that Diderot was obliged to do most of the work himself while smarting under the abuse that was heaped upon him by the officials of both the Church and the State.

Today copies of his Encyclopedia are quite rare. Not because so many people want them but because so many people are glad to get rid of them. The book which a century and a half ago was howled down as a manifestation of a pernicious radicalism reads today like a dull and harmless tract on the feeding of babies. But to the more conservative element among the clergy of the eighteenth century, it sounded like a clarion call of destruction, anarchy, atheism and chaos.

Of course, the usual attempts were made to denounce the editor-in-chief as an enemy of society and religion, a loose reprobate who believed neither in God, home or the sanctity of the family ties. But the Paris of the year 1770 was still an overgrown village where every one knew every one else. And Diderot, who not only claimed that the purpose of life was “to do good and to find the truth,” but who actually lived up to this motto, who kept open house for all those who were hungry, who labored twenty hours a day for the sake of humanity and asked nothing in return but a bed, a writing desk and a pad of paper, this simple-minded, hard-working fellow was so shining an example of those virtues in which the prelates and the monarchs of that day were so conspicuously lacking, that it was not easy to attack him from that particular angle. And so the authorities contented themselves with making his life just as unpleasant as they possibly could by a continual system of espionage, by everlastingly snooping around the office, by raiding Diderot’s home, by confiscating his notes and occasionally by suppressing the work altogether.