tronvillain

Let's look at the premise you're trying to use to dodge my argument:
You assert that "nonzero probability" in this case does not mean "probability one" but can you support that assertion? Let's have a look at what would happen if you tried various probabilities:

In other words, it is exactly as I said - your premise attempts to distance "nonzero probability" from "probability" one by stating what is already implicit. If determinism is true, the only nonzero probability an event can have is one. In order for this premise to be combined with the second premise, it must also use "nonzero probability" to mean "probability one." If it does not, then the argument does not follow.

Now, I think it should be apparent to anyone reading this thread that your argument is a total failure.

[ June 06, 2002: Message edited by: tronvillain ]</p>

Taffy Lewis

tronvillain:

Yes. If "nonzero" meant "one" then any number that was NOT ZERO would be equal to one. "0.25" is NOT ZERO. So following your logic "0.25=1". This is nonsense. "Nonzero probability" means any probability that is not zero. It is obvious that this does not mean the same thing as "probability of 1".

The 3rd premise says nothing more than that "Any event which does not have a probability of zero has a probability of one." You can substitute "event which does not have a probability of zero" for "nonzero probability".

Thus, "can" means "nonzero probability" in premises 2 and 3.

You seem to think that premise 3 is defining what "can" means. It is not.

The weakest premise seems to be premise 2 rather than 3. You'd do better to focus on that.

Is it really obvious that "Whatever should be done can be done."? It seems true but maybe there are important counter-examples.

[ June 07, 2002: Message edited by: Taffy Lewis ]</p>

tronvillain

As I have repeatedly pointed out, if determinism is true, there is no other nonzero probability than one! Look at what I showed you earlier about "If determinism is true, then whatever has a nonzero probability of being done, has a probability of one that it will be done":
It is apparent that premise three does not use "nonzero probability" in the same sense as premise three, since in premise three any nonzero probability will do, while in premise two a single nonzero probability is required. Since this is the case, the argument simply does not follow. Oh, you could make it follow by adopting the same meaning of "nonzero probability" in premise three, but no one wants to pervert the meaning of "should" like that.

Taffy Lewis

tronvillain:

"Whatever has a probability of one of being done, has a probability of one that it will be done." is true whether determinism is true or not. But this is not what the third premise says.

Further, it is not true that "nonzero" means the same thing as "0.9" or "0.5" or "0.1". Again, if that's what "nonzero probability" means then 0.9=0.5=0.1 and this is clearly absurd.

"Nonzero" means nothing more and nothing less than "is not zero". If what you are saying is true then we should be able to substitute "0.9" with "nonzero" and the sentences would mean the same thing. Obviously we cannot do this.

The third premise says that if determinism is true then any event that does not have a probability of zero must have a probability of one. This follows directly from the determinism thesis that there are no alternatives to what actually happens.

So we have:

Premise 2: "Whatever should be done does not have a probability of zero of being done (CAN BE DONE)."

Premise 3: "If determinism is true then any event which does not have a probability of zero (CAN BE DONE or nonzero probability) has a probability of one (IS DONE)."

Notice that the expression "does not have a probability of zero" appears in both premises.

Are you going to argue that "has a probability of one" means the same thing as "does not have a probability of zero" if determinism is true? That would suggest that determinism entails a contradictory claim. Since it is not contradictory something must be wrong with your analysis.

tronvillain

So, we are going to use these premises:

Premise 2: "Whatever should be done does not have a probability of zero."

Premise 3: "If determinism is true then any event which does not have a probability of zero has a probability of one."

Okay, that gives us:

"If determinism is true, then whatever should be done has a probability of one."

We can either accept this, and say that if determinism is true we use the word "should" incorrectly most of the time, or we can reject this and modify premise to to be more in line with common usage. This is because in retrospect, many of the things we say should be done turn out to have had a probability of zero.

If we go the first route and say that if determinism is true we use the word "should" incorrectly most of the time (which makes little sense) and move on in the argument:

Premise 1. "We should refrain from believing falsehoods."

We add it in and get "If determinism is true, the probability of us refraining from believing falsehoods is one."

Since this is obviously false, if determinism is to be true we must reject premise one (assuming we made the rather dubious decision of accepting premise two). Of course, this isn't hard given the definition of "should" we are then forced to use: "If whatever should be done has a probability of one, then it is not true that we should refrain from believing falsehoods, unless the probability of us doing so is one."

If determinism is true, then either premise one or two must be false. While premise one or two are both superficially plausible, one you get into the argument is is trivial to show how they could be false.

Taffy Lewis

tronvillain:

I don't see how this can be a definition of "should" since the term "should" appears twice in the definiens.

When you tell someone that they should do something do you really have in mind the notion of determinism as part of the very meaning of the word "should"? (Part of your "definition" of "should" involved the notion of determinism.)

If not, what do you mean by "should"?

[ June 10, 2002: Message edited by: Taffy Lewis ]</p>

tronvillain

Oh, that's not the definition of should, it is simply its logical application to the first premise. It is the combination of premises one and two that add to the definition of shoud: "If determinism is true, then whatever should be done has a probability of one." If you accept that assertion (I do not as I have already mentioned) then you can easily reject premise one, as I said: "If whatever should be done has a probability of one, then it is not true that we should refrain from believing falsehoods, unless the probability of us doing so is one."

tronvillain

Let's have a look at the original argument:

1)With respect to the free-will issue, we should refrain from believing falsehoods.

In general, refraining from believing falsehoods seems to be a good idea, though there can be exceptions.

2)Whatever should be done can be done.

Of course, if we accept this premise, we acknowledge that we may sometimes be wrong to say that something should be done.

3)If determinism is true, then whatever can be done, is done.

This is true by definition, at least under certain interpetations of what it is saying.

4)I believe that sometimes I can choose between alternative courses of action (ie. free will)

As far as I can tell, I don't just believe that I can choose between alternative courses of action, I do choose between alternative courses of action.

From 1 and 2 we get:

5)With respect to the free will issue, we can refrain from believing falsehoods.

Unless we are wrong in thinking that we should refrain from believing falsehoods with respect to the free will issue, for the reason that we are unable to refrain from believing falsehoods with respect to the free will issue.

From 3 and 5 we get:

6)If determinism is true, then with respect to the free will issue, we refrain from believing falsehoods.

Again, unless we are wrong in thinking that we should avoid believing falsehoods with respect to the free will issue, for the simple reason we are unable to refrain from believing falsehoods with respect to the free will issue.

Well, six uses "we" and four uses "I" but it probably follows. Of course, it is only true if it is true that you should refrain from believing falsehoods with respect to the free will issue, the truth of which is dependent on whether or not you actually can refrain from believing falsehoods with respect to the free will issue.

So, the argument comes full circle: If you can refrain from believing falsehoods with respect to the free will issue, then if determinism is true, you avoid a falsehood when you accept free will. If it turns out that you can't refrain from believing falsehoods with respect to the free will issue, then if determinism is true, you do not avoid a falsehood when you accept free will. This is an extremely unimpressive result.

The original argument finished off with:

8)I have free will.

8 is supposed to follow from 7 because believing in determinism is supposed to lead to a contradiction (ie. determinism's truth coupled with my avoiding a falsehood while believing in free will)

This assumes that "free will" is incompatible with determinism, but that does not follow from free will simply being defined as "the ability to choose between alternative courses of action."

To go back to the beginning, I quote myself:
[ June 10, 2002: Message edited by: tronvillain ]</p>

Taffy Lewis

tronvillain:

In an earlier post, you told me that I should accept your arguments if I want to be reasonable with respect to the free will issue. According to the above quote, your belief that I should accept your arguments is dependent on whether or not I can refrain from believing falsehoods with respect to the free will issue.

Therefore you think that I can refrain from believing falsehoods.

Assume I believe in free will and assume that if determinism is true then whatever I can do, I will do.

It follows immediately that I do refrain from believing a falsehood when I believe in free will.

If determinism is true then there cannot be any alternative courses of action. So they cannot be compatible.

tronvillain

Permit me to quote the most important part of my last post:
I have no idea if you actually can refrain from believing falsehoods with respect to to free will, and neither do you. Oh, it seems possible, but that doesn't mean it is actually possible.

That I said "And yes, if you wish to be reasonable, you should accept my arguments." means nothing when it comes to this arguments. I would have said it even if I knew for certain that you were incapable of accepting my arguments. I do not restrict my use of the word "should" to what is specified in your premises. Your argument is unimpressive - give it up and find another.

Taffy Lewis:
All I want the ability to select from the apparent alternatives, and determinism presents no obstacle to this. Suppose I have two pies, an apple pie and a pumpkin pie, and I choose to eat the pumpkin pie. Should I now complain that because of determinism I didn't "really" choose to eat the pumpkin pie or that eating the apple pie wasn't a "real" alternative? Such complaints are pointless - had things (myself and the world) been different, I might have chosen to eat the apple pie, but things were as they were, so I chose to eat the pumpkin pie.

What more is your version of free will supposed to offer? A magical coin flipper perhaps? A soulish random number generator? How would those things make me any more free than making a having my deterministic brain process the input and output a decision?