The Plates: Honoring Crafts and Useful Knowledge

Eleven volumes of the Encyclopédie contained no essays at all, only engraved plates, more than 2,500 of them, showing how things were made. They depicted papermaking, glassblowing, printing, weaving, mining, farming, pin-making and dozens of other trades in precise detail, often with a workshop scene above and labeled tools below.

Diderot visited workshops and interviewed artisans to understand their methods. The plates expressed a key Enlightenment value: practical, 'mechanical' knowledge was worthy of the same respect as learned theory, and craftspeople deserved recognition. Making trade techniques public could also help spread improvements and weaken guild secrecy.

Historians point out that the images are idealized: workshops look clean and orderly, and the hardship, danger and child labor of real work are largely absent. Some plates were also copied from earlier projects of the Académie des sciences, leading to accusations of plagiarism, but they remain an extraordinary record of pre-industrial work.