Can machines beg the question?

I thank Robert Oerter for his further reply to my recent comments (here, here, and here) on his critique of James Ross’s argument for the immateriality of the intellect.  You will recall that, greatly oversimplified, Ross’s argument is: (A) All formal thinking is determinate, but (B) No physical process is determinate, so (C) No formal thinking is a physical process.  You will also recall that Ross makes use of thought experiments like Kripke’s “quus” example to argue that given only the physical properties of a system, there can be no fact of the matter about whether the system is applying modus ponens, squaring, adding, or computing any other function.  That is what he means by saying that “no physical process is determinate.”  Finally, you’ll recall that among Oerter’s criticisms is that he thinks Ross is being inconsistent.  If we consider Hilda, a human being who can add -- or, as Oerter puts it in his latest post, who can ETPFOA (“execute the ‘pure function’ of addition”) -- then Ross’s argument would, Oerter says, apply to Hilda just as much as to a machine.  Yet Ross, Oerter claims, applies it to the machine but not to Hilda.  Hence the alleged inconsistency.

Oerter’s latest post summarizes his point as follows:

The logic of my Hilda example is straightforward. Ross says that humans can ETPFOA. Ross says that  A, B, and C entail that a computer cannot ETPFOA. I claim that A, B, and C are true for Hilda, too. So A, B, and C entail that Hilda cannot ETPFOA.

With this contradiction, the whole argument falls to pieces. Now, you can argue that I am wrong: that A, B, and C are not true of Hilda. Or you can argue that there is some D that I missed that is true of the computer but not true of Hilda. But you can't say this example is irrelevant to the soundness of Ross's argument.

End quote.  The problem, of course, is that Oerter is blatantly begging the question here.  A, B, and C entail that a computer cannot ETPFOA given the further premise that a machine is purely physical.  And that is a premise that both sides agree on.  But A, B, and C would entail that Hilda cannot ETPFOA only given the further premise that Hilda is purely physical.  And that is something both sides do not agree on; indeed, it is the whole point at issue.

The irony is that Oerter accuses Ross (or at least a reader who defends Ross) of begging the question.  But Ross is doing no such thing.  He would be begging the question in a way parallel to Oerter’s blatant begging of the question only if the further premise he needed was the premise that Hilda is not purely physical.  But that is not the premise he appeals to, and it is not the premise he needs.  Rather, what he needs and what he appeals to is the further premise that Hilda engages in formal thinking.  That premise together with A, B, and C is what generates the conclusion -- not a question-begging assumption but rather a demonstrated result -- that Hilda is not purely physical.

A, B, and C are, after all, only the heart of Ross’s position.  A little more fully spelled out, his overall argument essentially goes something like this:

A. All formal thinking is determinate.

B. No physical process is determinate.

C. No formal thinking is a physical process. [From A and B]

D. Machines are purely physical.

E. Machines do not engage in formal thinking. [From C and D]

F. We engage in formal thinking.

G. We are not purely physical. [From C and F]

The argument is valid, so to undermine it Oerter will have to reject at least one of the premises.  Premise A is one that Oerter has so far not challenged, and Ross defends it by arguing that we cannot coherently deny it.  Premise B is one that Oerter has also so far not done much to challenge.  His strategy was, at first, to suggest (wrongly, as we have seen) that the premise was really epistemological rather than metaphysical.  That failed, and Oerter shifted his focus to trying to argue that Ross was inconsistent in not drawing from B the same conclusion about human beings that he drew about machines.  As we have also seen, that would be irrelevant to the question of whether B is true even if Ross was being inconsistent.  But another thing we have seen is that Ross is not being inconsistent.

So, Oerter has given us no reason to doubt B, and thus he has given us no reason to doubt that Ross has established C.  D, as I have noted, is a premise both sides agree on.  Hence Oerter has also given us no reason to doubt that Ross has established E.  F is a premise which is not only agreed to by both sides -- at least, I assume that Oerter will agree that we engage in formal thinking -- but it is another premise we cannot coherently deny.  Since G follows from these premises -- premises which, again, Oerter has so far given us no reason to doubt -- he has therefore given us no reason to doubt G.  Ross, meanwhile, has given us very good reason -- I would say conclusive reason (for reasons I explain at length in my ACPQ article on Ross) -- to affirm his premises.  Hence he has given us very good reason to affirm G.

So, the score so far is still Ross: 1, Oerter: 0.  1s and 0s being fitting, I guess, given that it’s computers we’re talking about.