If, as we think, moral laws are to be binding on all rational beings, they must follow from universal principles of rationality. Good Will and only a good will is unconditionally, absolutely, or intrinsically good. Kant distinguishes two different types of non-intrinsic or extrinsic goods. Gifts of fortune include wealth, power, honor, health, happiness. All of these except happiness are reminiscent of Aristotle's external goods, although even happiness could be understood to fall into this class, if happiness, as Aristotle suggests, has such external goods of fortune as its necessary conditions.
Extrinsic goodness is a kind of accidental or contingent property of a thing.
If a thing is only extrinsically good, then it is possible for that thing not to be good, or to be bad or evil, without ceasing to be the thing that it is. It is not essential to what the thing is that it be good. Since the extrinsically good thing is not inherently good, since its goodness does not belong to it according to what it is within itself, its goodness must be due to something else. For if a thing is extrinsically good, then given the relevant bad-making external factor, it can become extrinsically bad. Such things are essentially neither intrinsically good or bad.