Definition
Non-Life
Non-Life refers to matter and systems that do not exhibit the characteristics of self-modification, dynamic stability through replication, or symbiotic complexification.
The Boundary of Life
In What Is Intelligence?, the boundary between life and non-life is described as ill-defined and potentially arbitrary. Rather than a binary distinction based on a specific “vital force,” the difference is one of computational degree and dynamical properties (Levin also argues for thinking about life/consciousness in intervals).
- Dead Matter: Matter in thermodynamic equilibrium or subject to simple linear degradation.
- Imperfect Replicators: Entities like autocatalytic chemical sets or “scrappy” programs in a turing gas that exhibit some life-like properties but lack robust heritability.
- Viruses and Parasites: Often classified as non-life because they lack independent reproductive machinery, yet they are integral parts of the symbiotic network of functions that constitute the biosphere.
Observation
The transition from non-life to life is a “weaving together” of many separate strands. Because life is defined by its networks of mutually beneficial relationships, a system can be considered more or less “alive” depending on the scale and complexity of its homeostatic feedback loops (see gaia hypothesis).