Rules for the Direction of the Mind (Latin: Regulae ad directionem ingenii) is a book by René Descartes. It was written about 1628. It was not finished, because 36 rules were planned in all, but only 21 were actually written. This work was not published while the author was alive. The Rules were published in 1701 in Amsterdam.
Many ideas in this book reappeared, year later, in the Discourse on the Method.
Although young, Descartes in times of Regulae had already believed in innate ideas, for example of the mathematical truths.