Maybe along with Kolmogorov complexity we could measure &quot;usefulness&quot; of a bit string, i.e. how much utility an agent would agree to pay for it. The idea is that &quot;complex&quot; things, like life, are likely to contain solutions to many problems we care about. Of course that approach depends on the agent, but maybe you could get a general definition by referring to a general agent, like AIXItl.