There are many different ways this closeness to life, or "aliveness", 12 could be characterised, one of which is the level of self-control exhibited by an individualised chemical system. In life as we know it, an important component of this self-control is kinetic control, usually achieved through enzymes. The greater the extent to which a chemical system exerts control over itself and its immediate environment, the more we might consider it to have greater aliveness. Thus, kinetic control seems to be a necessary condition for life, though it is far from a sufficient condition.