Friday, January 10, 2014

Vincent Cheung and Modus Tollens

If p, then q. ~q. Therefore ~p

In thinking in general, and philosophy and theology in particular, logic is very important. Logic is the way we think, formulate arguments and prove our theses. Without logic, not only can there be no reasoning, but even words are meaningless since they can mean both A and ~A (not A), or X.

The problem with much of contemporary discussion is that logic is overlooked and even demeaned, and those who are logical are labeled and maybe shunned as "rationalists" (proving that those applying the label have no idea what they are talking about). Logic however has a way of returning with a vengeance, and those who neglect it will pay the price when their arguments fail.

I am currently having an email discussion concerning Vincent Cheung's heresy on theodicy. Part of my argument deals with the issue of unacceptable consequences, which somehow my correspondent fails to get.

This is where basic logic comes into play, which is extremely funny and ironic since Vincent Cheung supposedly priced logic. The argument against Cheung's supposition that God is the author of sin is in the form of a modus tollens, as follows:

p: God is the Author of Sin
q: God's will is divorced from God's nature, or God is evil
If p, then q; ~q, therefore ~p

So the argument is set simply as such. If the conditional statement is true (If p, then q), then a rejection of q must necessarily result in a rejection of p as well. It is altogether irrelevant for one to subsequently claim ~q, that God is good by definition. That is a separate claim that stands in tension with this particular argument. If one insists, as Cheung does, on claiming that God is not evil because of He is good by definition, what does this claim do? It does not vitiate the initial argument at all! Rather, it creates a new argument as follows:

If p, then q. p; ~q; therefore p.

As it can be clearly seen, such an argument is nonsense, for it is logically contradictory and invalid.

Now, one can dispute the truth of the conditional statement, but such is easy to be proved. If God is the Author of evil, which is to say he directly causes evil, then he must do so because his action in causing evil has no relation with his good and pure nature, or that his nature is evil. These are the only two possibilities. Either God is good but does evil, or he is evil and does evil. That is the basic logical law of the excluded middle, and is thus non-negotiable. So if God is evil and does evil, God is evil. But if it were to say that God is good and yet he does evil, then there must be no relation of his nature to his will; the two are divorced from each other. The conditional statement therefore is proven true.

But then the proposition q is actually two propositions, and are both necessarily false? Let us have q1 = God's will is divorced from God's nature, and q2 = God is evil. q2 is most certainly to be rejected. But what about q1? If q1 were to be true, then God's actions are totally arbitrary, since there would be no necessary relations between God's actions and who God is. Is that however how the Scripture portray God? Don't we see the Scripture proclaim who God is as the basis for what He will do for His people? In Numbers 6:23, God's faithfulness and truthfulness and immutability (His nature) function as the basis for why God will do what He has spoken and promised. However, if we have the "God" of Vincent Cheung with his arbitrary actions, God could continue to be faithful, truthful and immutable, but he could change his mind (action) and decided not to fulfil his word. Judge for yourself whether proposition q2 is true to Scripture! It is most certainly not!

That is why everyone should have a course in basic logic, for it exposes a whole bunch of nonsense that tries to pass itself off as something profound. Cheung's theodicy is unbiblical, because its consequences contradict the express teachings of Scripture. It is sad that even such a basic argument in my first article needs to be clearly enunciated in another blog post, which just goes to show how illogical people are.


Unknown said...

For God to cause evil does not mean that He commits evil. If you insist that the inverse is true, then explain how evil is caused and who is behind it. Be careful that you do not fall into dualism.

Daniel C said...


nobody says that for God to cause evil He commits evil. Interact with the actual argument please.