This is basically noted in this book, this book, this book, as well as by philosophers who specialize on TAs, such as Genova, Chisholm, Strawson, et. al.
A while back Dr. Moore tried to show that Van Til committed a school boy fallacy -affirming the consequent. Here is the gist of his post:
Van Til's claim that, "The only "proof" of the Christian position is that unless its truth is presupposed there is no possibility of "proving" anything at all" should be translated like this:
3. :. P" (Moore's translation of the above).
Moore's conclusion: "Aha! Again we see Van Til’s fallacy of Affirming the Consequent. Paul has tried to hide this fallacy, but the illusion doesn’t last."
I had responded thus:
Certainly this is valid, but Zach doesn't know how to translate arguments into proper form. An argument having the form "p unless q" has three equivalent propositions
p unless q
p if not-q
if not-q, then p
Consequently, "p unless q" is exactly equivalent to "if not-q, then p," and should be translated that way (cf. any text on logic). (Note, sometimes you can translate "p unless q" as "p v q," depending on context. But, this is a disjunct and so does not help Moore's formulation, anyway. Put differently, if we translate Van Til's statement into a disjunctive syllogism Moore still fails.)
So, we can see that Moore's formulation: ~p --> ~q, q, :. p is an improper translation. The proper translation would be ~q --> p. Then from here one could either go: ~p, :.q, or ~q, :. p.
Now, Dr. Moore is still trying to find problems with the formulation of TAG (Note that if he does then he finds problems with all the philosophers I mentioned above. Likely?).
Most recently, Dr. Moore attacks a friend of mine, Pastor Dustin Segers, and tries to show that Segers is another moron who affirms consequents. Moore takes something Segers writes and subjects it to Moorean analysis.
Dustin had written:
1) For X to be the case, Y has to be the case.
2) X is the case.
3) Therefore, Y is the case.
And Moore responds,
"Read that first premise to yourself slowly a few times. Does that seem strange to anyone? This is not the standard language used to make a conditional statement. The standard language would be:
"If X is the case, then Y is the case."
Well, part of learning logic is to be able to translate ordinary language into "standard language."
Moore than translates the above as:
1) If Y is the case, then X is the case.
2) X is the case.
3) Therefore, Y is the case.
And pats himself on the back, writing: "Now we can easily see that this argument takes the form of the logical fallacy Affirming the Consequent."
Moore's main beef is with what he calls Dustin's "for-has" language. Since Dustin said For X ... Y has... then Moore thought that gave him the right to translate the argument as affirming the consequent.
Well, Moore's post was silly and so I never bothered to respond.
But this caused Moore to gloat: "No presuppositionalists want to weigh in on this before it slips off the front page? Well, I guess I had it right, then."
Besides the argumentum ad ignorantium, Moore's attitude makes one laugh. Moore then bragged about his decimation of Dustin on John Loftus' blog. So I thought I would help the good doctor out. I simply said,
"Dustin said, For X to be the case Y *has* to be the case. This shows that Y was the necessary proposition. When translating a conditional proposition, you place the sufficient condition in the antecedent position and the necessary condition in the consequent position."
I also asked Moore to back up his translation from a logic text.
Moore's response was not to admit that he was wrong (which should give us pause when we argue with him, knowing that he's out to preserve himself and atheism, at all costs. Truth, whatever that is, takes the hindmost) but rather he said,
"If I'm wrong, show that I'm wrong. You're still doing nothing but sniping and complaining. Which is it- is X dependent on Y or is Y dependent on X? Show me the logic book that lets you construct a syllogism that way."
Again, when translating a hypothetical conditional the necessary proposition goes in the place of the consequent, Moore! Dustin's use of the phrase "has to be" should have been enough for Moore to translate it properly. That is, if Moore has a modicum of understanding about logic. Moore wants me to back this up?
Stanford Encyclopedia of Philosophy offers support. Here's a quote:
The front door is locked. In order to open it (in a normal, non-violent way) and get into the house, I must first use my key. A necessary condition of opening the door, without violence, then, is to use the key. So it seems true that
(i) If I opened the door, I used the key.
Can we use the truth-functional understanding of "if" to propose that the consequent of any conditional (in (i), the consequent is "I used the key") specifies a necessary condition for the truth of the antecedent (in (i), "I opened the door")? Many logic and critical thinking texts use just such an approach, and for convenience I call it "the standard theory" (see Blumberg 1976, pp. 133 - 4, Hintikka and Bachman 1991, p. 328 for examples of this approach).
The standard theory makes use of the fact that in classical logic, the truth-function "p ⊃ q" ("If p, q") is false only when p is true and q is false. The relation between "p" and "q" in this case is often referred to as material implication. On this account of "if p, q", if the conditional "p ⊃ q" is true, and p holds, then q also holds; likewise if q fails to be true, then p must also fail of truth (if the conditional as a whole is to be true). The standard theory thus claims that when the conditional "p ⊃ q" is true the truth of the consequent, "q", is necessary for the truth of the antecedent, "p", and the truth of the antecedent is in turn sufficient for the truth of the consequent. This relation between necessary and sufficient conditions matches the the formal equivalence between a conditional formula and its contrapositive ("~q ⊃ ~p" is the contrapositive of "p ⊃ q". Descending from talk of truth of statements to speaking about states of affairs, we can equally correctly say, on the standard theory, that using the key was necessary for opening the door."
Another source would be Wikipedia. Here's a quote: "The truth of the antecedent is a sufficient condition for the truth of the consequent, while the truth of the consequent is a necessary condition for the truth of the antecedent."
Another source would be from
the thinking shop (under the section, "tips for translating." As a side, notice that they have a section called "translating." When I used this word for translating for-has to if-then, Moore mocked me, saying: "I do think it's really funny to talk about "translating" English to English. Somehow "for-has" to "if-then" is "translating." You're a riot." Get that! Moore doesn't even know that that is what it is called. What a riot that guy is).
And so with that said, I think it is fitting to end with something Steve Hays said chestnuts (I'll just replace Loftus with Moore:
Thus far, the chief threat which Zachary Moore poses to the church is that Christian intellectuals will become cage fat from the yummy diet of intellectual junk food he’s been dishing up for our consumption.
We’ve never had it so easy. We no longer need to write original essays. We simply mouse over to his blog once a day, and he supplies us with all the honeyed corn mush we need to do a post of our own.
I’d advise my fellow bloggers not to become overly indolent from living off the fat of the land. Rather, we should squirrel away this bountiful summer’s harvest of warmed over chestnuts for the lean months to come. It’s just too good to last. Rationing is the only prudent policy. “Chestnuts roasting on an open fire…”