Emergent property
From Memory Alpha, the free Star Trek reference.
An emergent property can be described by the following, "complex systems can sometimes behave in ways that are entirely unpredictable. The Human brain for example, might be described in terms of cellular functions and neurochemical interactions. That description does not explain Human consciousness, a capacity that far exceeds neural functions. Consciousness is an emergent property. In other words, something that's more then the sum of its parts." (TNG: "Emergence")
