André Leroi-Gourhan

André Leroi-Gourhan brought the rigor of paleoanthropology and the breadth of comparative ethnology to the question of technology's origins, producing in Gesture and Speech the most empirically grounded account of the link between human anatomy, tool-use, and language. His starting point is the decisive biological event of bipedalism: when the genus Homo moved to upright walking, the anterior limbs were freed from locomotion and the skull balanced atop the spine in a new configuration that permitted brain expansion and the elaboration of the facial organs — tongue, lips, and the fine musculature of the mouth. The hand and the face were freed simultaneously, and Leroi-Gourhan insists that this simultaneity is not coincidence: tool and symbol co-originated.

Leroi-Gourhan developed the concept of 'exteriorization' to describe the long process by which the human being progressively transfers cognitive and physical capacities outward into technical objects. The hand externalizes gesture into the tool; language externalizes memory into speech; writing externalizes speech into graphic marks; and the computer, he foresaw, would externalize the very process of cortical association. Each stage of this exteriorization is simultaneously biological, technical, and social: the tool changes the body's relationship to the world and opens new neurological possibilities that feed back into further technical development. For Leroi-Gourhan, the origin of technology is therefore inseparable from the origin of the human species itself — they are, strictly, the same event viewed from two angles.