Saturday, October 14, 2006

The Ubiquity of Apriority

Some philosophers are skeptical of whether there can be a priori (non-empirical) justification. But I'm not sure how they can avoid it. For any instance of empirical justification, it seems like we can construct a parallel instance of a priori justification simply through conditionalization. Suppose that empirical evidence E would justify your drawing conclusion C. Then presumably you could justifiably believe the conditional "if E then C" prior to experiencing E. We can repeat this procedure to conditionalize out all empirical grounds for belief, and the result will be a conditional statement that is justifiable a priori.

Bonjour suggests something similar in In Defense of Pure Reason, p.5:
Could an argument of any sort be entirely justified on empirical grounds? It seems clear on reflection that the answer to this question is "no." Any purely empirical ingredient can, after all, always be formulated as an additional empirical premise. When all such premises have been explicitly formulated, either the intended conclusion will be explicitly included among them or it will not. In the former case, no argument or inference is necessary, while in the latter case, the needed inference clearly goes beyond what can be derived entirely from experience. Thus we see that the repudiation of all a priori justification is apparently tantamount to the repudiation of argument or reasoning generally, thus amounting in effect to intellectual suicide.

What response can the radical empiricist make to this?


  1. I also find anti-a priori views weird, but I'm not sure one can give conclusive attack on those view by logic/intuition as logic/intuition would not be a priori too. I find it similar to skepticism, that while maybe consistent within itself, it seems that it ignores something.
    So maybe some scheme which are usually applied to skepticism may be used here. For example:
    For sure theory there is no a-priori can not be a-priori.
    Hence it can be wrong.
    Hence there might be a-priori.
    Hence the theory that there is no a-priori is wrong.

  2. Oops, I was thinking of the stronger version "there can be no a priori" in the argument. The argument for sure won't work for a weaker version "there is no a priori".
    But the skeptics about apriority are, I guess, arguing the weaker position.

  3. I think blocking the intelligibility of global justification blocks both your and Bonjour's argument. If justification is coherence-based (as Bonjour used to think), then while you can ask whether particular evidence E justifies belief B, this will be based on other empirical knowledge. Then the conditional will be justified by that empirical evidence. You can't ask whether all your beliefs are justified by all your evidence, because there's no way of evaluating that, and so you don't have any a priori knowledge that if you have all your evidence, you are justified in your beliefs generally.

    In the case of Bonjour's argument, it is even more clear that the unacceptable conclusion is that there is no justification link between total evidence and any beliefs that go beyond that, so if the absence of such a justification link is accepted, the argument fails. Since it is still possible to use parts of our web of belief to evaluate other parts, I do not see that this constitutes the abandomnent of reasoning Bonjour claims.

  4. I have a similar worry about the argument . I'm not certain that you must say that in order to be justified in believing p on e, you must be apriori justified in believing 'if e, it is rational to believe p', 'if e, then p' or any such thing. For one, you might think that all that is needed is the absence of reasons to doubt the connection between e and p. For another, there might be circumstances under which acquiring e simultaneously justifies you in accepting e and accepting e as evidence for p [No examples spring to mind, but it's been a long day].


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