Consilience: Consilience is intended to serve as a measure of how much a theoryexplains, so that we can use it to tell when one theory explains more of the evidencethan another theory. Roughly, a theory is said to be consilient if it explains at leasttwo classes of facts. Then one theory is more consilient than another if it explainsmore classes of facts than the other does. Intuitively, we show one theory to be moreconsilient than another by pointing to a class or classes of facts which it explains butwhich the other theory does not.A consilient theory unifies and systematizes. To say that a theory is consilient is to saymore than that it ”fits the facts”: it is to say first that the theory explains the facts,and second that the facts it explains are taken from more than one domain.