A human body is a conversation going on, both within the cells and between the cells, and they’re telling each other to grow and to die; when you’re sick, something’s gone wrong with that conversation.

Hillis frames the body as an information-processing system: health depends on continuous signaling—chemical, electrical, and genetic—within and among cells. Growth and programmed cell death (apoptosis) are not merely mechanical events but coordinated outcomes of this “conversation,” akin to distributed computation. Illness, in this view, arises when communication breaks down: signals are misread, absent, or amplified, leading to uncontrolled growth (as in cancer), inappropriate immune activation (autoimmune disease), or failure to repair. The metaphor emphasizes interdependence and regulation rather than isolated parts, suggesting that understanding and treating disease often means restoring correct signaling networks, not just targeting a single component.