By Schubert Ogden
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A priori christology is purely formal in that it explicates the necessary conditions that would have to be satisfied in order for the assertion, "X is the Christ," to be true for any value of the variable X. Unless a, b, c, etc. could be truly affirmed of X, the assertion, "X is the Christ," could not be a true assertion. Thus, if it belongs to the concept, "Christ," for example, that any X of which it is affirmed truly must be the explicit, primal, ontic source of all that is divinely authorized, then to say of any possible value of X that it is the Christ is to claim for it this unique function or role in the system of divine authorization. A posteriori christology, on the other hand, is not thus purely formal, but material – -- and that in two respects: in respect of asserting of the particular historical person, Jesus, say, that he satisfies all the necessary conditions that would have to be satisfied in order for the assertion that he is the Christ to be true – -- for example, that he is the explicit, primal, ontic source of all that is divinely authorized; and in respect of asserting of the meaning of ultimate reality for us what, because just this particular, historical person, Jesus, is the Christ, also has to be true of it.
This is not to question, however, that even the statement, "Jesus is the Christ," is itself, in a way, purely formal unless and until the material meaning of "Jesus" is unpacked. All the statement asserts is that whatever is meant by "Jesus" is the Christ. But that remains purely formal so long as what is meant by "Jesus" is left unclear. Only when it is clarified does the statement assert the material meaning of ultimate reality for us that it is intended to assert – -- together with asserting (purely formally) that the particular, historical person, Jesus, is of decisive significance for human existence.
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