Artificial Life

Artificial life (ALife) is the study of life and life-like processes through the synthesis and simulation of biological phenomena in artificial media — computers, robots, and chemical systems. Rather than analyzing existing biological organisms, artificial life attempts to construct systems that exhibit properties characteristic of living systems: self-replication, evolution, adaptation, and autonomous behavior.

The Two Approaches

Soft artificial life uses computer simulations to study evolutionary and ecological dynamics. Cellular automata, genetic algorithms, and agent-based models are the primary tools. The classic example is the Game of Life, a cellular automaton in which simple rules produce complex, self-organizing patterns that resemble living processes.

Hard artificial life builds physical systems — robots, chemical protocells, and evolutionary hardware — that instantiate life-like processes in material substrates. This approach takes embodied computation seriously: it holds that certain properties of life, particularly autonomy and situatedness, may require physical instantiation.

The Open Question

The central question of artificial life is whether the properties that distinguish living from non-living systems are substrate-independent (computable in any sufficiently complex medium) or substrate-dependent (requiring specific physical or chemical properties). This is the same question that divides functionalism from biological naturalism in the philosophy of mind, applied to the phenomenon of life itself.

Artificial life is not merely a simulation of biology. It is an attempt to discover the logical and physical prerequisites for life — to ask what life is, by making it.