Use your brain as well as your hand.

Sers toi aussi bien de ton cerveau que de ta main.

Notes from Wikiquote

Les aliments biologiques (Lyon, Edition Camugli, 1982, ISBN 2-851-83000-7), p. 67

Quote text and notes from Wikiquote: Jean-Claude Rodet (page history), available under CC BY-SA 4.0. Source quality and labels are our own summary of what Wikiquote records.