1.) Assumption: Objects and events affect our thoughts and beliefs. The determinist believes this, because it must be an object or event which determines thought. The non-determinist also believes this, because to think about something is to be influenced by it. Thus, everyone accepts that there is some influence over our thoughts on the part of external factors (debate being over its degree).
2.) Either your thoughts are deterministic, or not. (Excluded middle)*
3.) Plantinga has argued against thought determinism -- in that one cannot claim to have arrived at this belief through reasoning.† If determinism is true, you can't be correct about it (in contrast to being wrong about it) -- you are merely 'caught up in a particular causal stream.'
∴ If you believe in absolute determinism, there is no sense arguing. You might still argue (you would be fated to do so), but there is no sense in it.
If there is no sense in arguing, I shall adopt the Bartleby approach. I would simply prefer not to argue. One thing a determinist cannot do is accuse me, in imitating the scrivener, of being unreasonable. Actually, the determinist can so accuse (he would be fated to do so). He simply cannot do so in the form of a complaint that is itself reasonable.
But if it is not reasonable to enter into the arena of discourse (what more could an argument do beyond the bandying about of atoms?), what is a reasonable response?
Ibn Sina (whose name inexplicably gets a different number of ns when Latinized as Avicenna) is reported to have said that someone who denies the law of contradiction should be beaten and burned until he admits that being beaten is different from not being beaten and being burned is different from not being burned.‡
I for one am in favor of this Kalam response to determinism. In my fantasy world, I would put Pyrrho in charge of listening to complaints about this.
* Here, by "deterministic" I mean that one's thoughts are fully determined by efficient causes. As already mentioned, belief in free will does not preclude the fact that some events are determined by efficient causes.
† Citation needed
‡ Citation needed
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