Distinguishing two theses in Anscombe's reply to C. S. Lewis

 From an essay I am writing on the Anscombe legend. 

Now most of Anscombe’s argumentation is aimed at establishing what I will call thesis A:

A) The argument Lewis presents in the third chapter of the first edition of Miracles overlooks some crucial distinctions, and therefore fails to show that naturalism is incompatible with the validity of reasoning.

However, at the end of her piece Anscombe goes on to say the following:

I do not think that there is sufficiently good reason for maintaining the “naturalist” hypothesis about human behaviour and thought. But someone who does maintain it cannot be refuted as you try to refute him, by saying that it is inconsistent to maintain it and to believe that human reasoning is valid and that human reasoning sometimes produces human opinion.

In other words she asserts what I will call thesis B:

B) You cannot refute the naturalist position by saying his position is inconsistent to say that naturalism is true, that human reasoning is valid, and that humans reasoning sometimes produces human opinion.

This goes beyond saying that Lewis didn’t refute naturalism because he overlooked the distinctions Anscombe insisted upon, this is to say that you can’t refute the naturalist on the basis of the validity of reasoning, because of these distinctions. 

            Did Lewis concur with A? Almost certainly he did. I have known some philosophers who have thought that Lewis really didn’t need to revise his chapter at all, including the late philosopher Richard Purtill, but Lewis did not concur. (Neither would I).  Even in his initial brief response to Anscombe’s critique, which was published in the same issue of the Socratic Digest in which her essay appeared, he acknowledged the difficulty surrounding the use of the term “valid” and employed one of Anscombe’s central distinctions, between the cause and effect because, and what  he called the ground and consequent because. He indicated in his reply to Norman Pittenger that the third chapter of Miracles contained a “serious hitch” and that it “needs to be rewritten.” Establishing A is a good day’s work for a philosopher, particularly in that she persuaded the very person to whom she was responding that one of his central arguments, as stated, had serious problems and needed to be reworked.

            Now, if this is what winning the debate amounts to, Anscombe won, and Lewis agreed that she did. But she did go on to assert B, and if winning the debate requires establishing B, Lewis dissented. He wrote in his short response in the Socratic Digest:

It would seem, therefore, that we never think the conclusion because GC it is the consequent of its grounds but only because CE certain previous events have happened. If so, it does not seem that the GC sequence makes us more likely to think the true conclusion than not. And this is very much what I meant by the difficulty in Naturalism.

Lewis would go on to make this claim the centerpiece of his argument when he revised the chapter. He wrote:

But even if grounds do exist, what exactly have they got to do with the actual occurrence of the belief as a psychological event? If it is an event it must be caused. It must in fact be simply one link in a causal chain which stretches back to the beginning and forward to the end of time. How could such a trifle as lack of logical grounds prevent the belief’s occurrence or how could the existence of grounds promote it?

            I am inclined to be resistant to talking about winning and losing in philosophical debates. They are not football games.  The Christian philosopher and apologist William Lane Craig often does public debates on apologetical issues, and usually comes out looking better than his opponents. But skeptics have complained, with some justification, that doing well in a public debate format is not the same as proving one’s central thesis to be true from a philosophical standpoint. Now, if we are going to assess a winner in the exchange, there are, as Bassham notes a few different ways this can be assessed. Do we look just at the exchange on that day in at the Oxford Socratic Club, or do we look at the overall exchange between the two parties over time? Do we go by what the audience thought had happened? In a couple of important senses, Anscombe was the clear winner, especially if you look only at what happened on Feb. 2, 1948. There is no reason to doubt Carpenter’s report that many in the audience thought that a conclusive blow had been struck against one of Lewis’s fundamental arguments. On the narrow question of whether Lewis’s formulation of the argument is philosophically adequate, Anscombe contended that it wasn’t, and Lewis agreed. However, the most interesting philosophical question of whether or not you can refute naturalism based on the validity of reasoning cannot be settled the outcome of a particular exchange at a debating club. When Walter Hooper asked Lewis if he said he lost the debate with Anscombe, and Lewis said he didn’t, Lewis was probably thinking in terms of the question of whether Anscombe had shown that B is true. He was convinced that she had not. And looking at Anscombe’s responses to Lewis’s revised work, both in the introduction to her collected papers, and in her longer response given to the Oxford C. S. Lewis Society in 1985, she does not reassert B. So far as I can tell from her responses, she does not think that Lewis had established that B is false, but she no longer confidently asserted that B is true. I would summarize this by saying that I think Anscombe won a significant, but only partial, victory, and in this I believe Lewis would concur.