By Schubert Ogden
Although asking about the fittingness of a particular instance of Christian witness to its situation is as proper a theological question as asking about its adequacy to its content (i.e., its appropriateness to Jesus Christ and its credibility to human existence), this is not the case with asking about either its efficacy or its effectiveness to a particular person. The adequacy of a witness to its content and its fittingness to its situation are both matters of validity and, as such, can be properly determined theologically, i.e., by a certain kind of critical reflection involving a certain kind of critical interpretation as well as a certain kind of critical validation. But the validity of a witness is one thing, its efficacy as well as its effectiveness, something else, in that neither can be determined by critical reflection, because both are dependent on the existence of a particular person -- on person—on her or his existential experience, in the case of efficacy, and on her or his existential decision, in the case of effectiveness.
This means, among other things, that the question I once raised (cf.. , September 1987), whether it mightn't be better to speak of witness's being "effective in its situation" than of its being "fitting to its situation" is misleading -- and misleading—and misled. This is so, at any rate, if one distinguishes "validity" from both "efficacy" and "effectiveness" in the way in which I've now come to do (ccf.f. , "On Efficacy as Distinct from Validity and Effectiveness," 31 December 2002).
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