Chris: Are you a believer?
Well it’s nice to have one of those around every now and then.
We have to get Christians from somewhere after all.
So I presume you have heard the Christian Gospel?
Go to mass… et cetera
Chris: I’m guessing that you’re joking.
Atheist: I am
Chris: So why are you an atheist?
Atheist: I don’t think that any spirits exist
be they gods, ghosts or anything else
Chris: That’s the definition of your position then.
Why do you hold it?
Atheist: I don’t see any evidence for the existence of them, and from what we know things that are attributed to them are based on brains
Chris: So would you say that you live by something like, “In order to rationally believe a proposition X, there must be evidence to support X”?
Chris: What would be your evidence for that principle?
Atheist: well, it’s more of a definition of being rational, isn’t it?
Chris: I don’t accept it, no.
And most philosophers do not.
But even if it is, then according to that statement, we must have evidence to believe it.
well, we can just define “being rational” as “believing propositions that have evidence to support them”
What evidence supports the claim, “Being rational is believing propositions that have evidence to support them”?
Atheist: I don’t know if that’s a claim or just a definiton :S
Chris: It’s both.
But even if it’s a definition, I see no reason or evidence being offered to accept it.
Atheist: ok… then don’t
then you’ll just believe that being rational is accepting whatever you want to
Chris: I mean, I could just define God as “that being which exists.”
But you wouldn’t like that much, would you?
I didn’t say that being rational is accepting whatever I want to.
However, you seem to be operating with something like that in mind.
Because you have not told me yet why you accept that definition of rational belief.
Atheist: that being rational is accepting whatever I want to?
Isn’t that just what it means to be “rational”?
But I think you see the problem I’m getting at, whether you think it’s really a problem or not, so let me move on.
There are lots of things that we accept without evidence.
For example, the existence of other minds (even if the mind is merely brain).
What evidence is there for accepting that there are other minds?
Atheist: the classical example is: “How do you know you’re not in The Matrix?”
ok…and the point is?
Chris: The point is that you define rational as only accepting beliefs that have evidence to support them.
But that would mean you cannot rationally believe in other minds.
Unless, of course, you have evidence to support that belief.
Atheist: well, I don’t think other minds is a good example, but I like the Matrix one
Chris: Do you believe in other minds?
Atheist: I believe other people have experiences, are conscious and so on, yes
Okay, what evidence do you have for that belief?
Atheist: what evidence do I have for that? well, for example if I hit my friend, he respons by saying “ouch, that hurt”… that seems to me to be a prima facie evidence for that
Chris: But that’s all possible through animation.
Perhaps your friend is a zombie of sorts, and it has nothing to do with mind, experience, or consciousness.
Atheist: well, we’re interested in what is probable, not what is possible
Chris: Right. And you need evidence to talk about what is probable.
I’d set the probability that your friend has conscious experience of the pain from hitting him at .5.
Because it’s just as likely he’s a zombie.
Atheist: why do you say that?
Chris: Because there’s no evidence to the contrary.
Atheist: I mean, you already have one example of someone who acts like that and isn’t a “zombie”
Chris: That’s correct.
But that’s not a very good sample size.
Atheist: how many examples do you have of actual zombies?
Chris: Perhaps many!
Atheist: do you know that any of them are zombies?
Chris: I don’t.
But nor do I know they are conscious.
Remember I said .5.
Atheist: ok, so from the known cases, 100% aren’t zombies
But what does that tell us about the unknown cases?
Atheist: and that has no effect on your estimates?
well, what reasons do you have to expect that the other cases are different from the known case?
the 100% known case
Chris: None, but that’s not the problem. We need evidence *in favor* of the proposition that they are the same as the one known case.
Atheist: Chris… there are no apparent differences… so why would you think that they work differently?
I mean, it’s like looking at two apparently identical computers, we know that one of them runs on electricity. Is that fact irrelevant when we are deciding if the other one runs on electricity or not?
Chris: You give me no reason to think that it is relevant.
Atheist: well, since all known examples are not zombies, I think the probability should be 1,0!
Chris: That leads us into another problem.
What do examined cases of anything in nature have to do with unexamined cases?
Atheist: is this going to be a discussion of the uniformity of nature?
We can go wherever!
What did you have in mind?
Do you believe in something like the uniformity of nature?
Chris: What evidence do you have for it?
Atheist: well, from what we’ve seen that’s the way the world works
But what about what we haven’t seen.
Atheist: earh has been spinning around the sun for billions of years for exampl
right… is there any reason for expecting them to change?
I mean they might… but they haven’t
…and of course presuppers make even bigger assumption, they assume the uniformity of ther god
Chris: Remember, you claim that you have evidence *for* your belief in the uniformity of nature. Now you’re asking me for evidence against. But that’s irrelevant.
What is your evidence *for* the earth spinning around the sun for even another day?
Atheist: well, I think if we do some experiment 999 times and get the same results, it’s probably going to give the same result the 1000 time
Chris: I don’t know what the uniformity of God is btw.
Atheist: you assume that god’s nature doesn’t change?
Chris: Ah, so the future is probably going to resemble the past.
Chris: What evidence do you have for your belief that the future is probably going to resemble the past?
Atheist: from what we’ve experienced the future does resemble the past
Chris: But you’re just talking about the past.
I would like to know about the future.
Atheist: well, it wasn’t past in the past, it was still the future!
Chris: What evidence do you have for your belief that the *future* is probably going to resemble the past?
Btw, I don’t have a problem presupposing (upon the basis of Scripture) that God doesn’t change. Remember, I’m not an evidentialist, you are.
Atheist: Chris, we have observed nature behaving in an uniform way for a long time, so if you are going to claim that it’s going to change, I think the burden of proof is on you
Chris: I didn’t make that claim.
You’re shifting the burden of proof again.
The onus is on you to provide evidence that the future will probably resemble the past.
Otherwise, your belief is irrational, by your standard!
You already tried that a minute ago, remember.
Atheist: Chris, nope, I think the past behavior is good evidence for the future
Chris: I see.
So if you flip a coin, and it lands heads up, the next flip it will do so again?
Atheist: well, if all the parameters are the same
e.g. if we have a robot coin-flipper that is consistent
Chris: I’m still trying to figure out how past behavior has anything at all to do with future behavior.
Atheist: so you want evidence for “past experience is a good predicter of future events”?
Chris: Well, that’s not how we stated the principle earlier.
But yes, something to that effect.
Atheist: well, then have we been able to successfully use past experience to predict future events?
Chris: In the past, yes.
What evidence do you have that it will continue to be that way in the future?
Atheist: right… so we have evidence for the principle: “past experience is good predicter of future events”!
Chris: See, I keep asking you about our expectations regarding the future, and you answer me concerning the past.
But I’m not asking you about the past.
I’m asking you about similar things obtaining in the future.
Atheist: we have had (in the past of course) evidence for past experience being good predictor for the future
so…there’s the evidence for you!
Chris: But that doesn’t have anything to do with the future.
You’re just assuming that since it’s been that way in the past, it will be that way in the future.
Frankly, you’re begging the question (when you’re not shifting the burden of proof).
Atheist: Chris, I think we have some reasons for accepting that proposition (it works!)… but no reasons for thinking it to be false… sure, we can’t be certain
Chris: I’m not even concerned about certainty.
I don’t see any evidence in your view for thinking that the future will *probably* resemble the past.
And even saying that it works assumes, again, that it will continue to work in the future.
So, like David Hume said, we’re just appealing to the very principle we’re attempting to justify.
So here are my thoughts: You claim that in order to rationally believe something, you need evidence for that belief, yet you have not given me any evidence for that belief itself (that definition), you have not given me any evidence (aside from yourself) for your belief in other minds, and you have not given me any evidence for your belief in the uniformity of nature. Yet you would say you rationally believe all these things. So either your principle is false, or you are inconsistent with it.
Atheist: well, I think the principle holds in this instance, although it doesn’t in other instances
Chris: In any event, the “no evidence” complaint wouldn’t really work against a position like mine, since I presuppose the existence of God, and hence also other minds and uniformity. More than that, there are the problems with your view I cited above.
But I appreciate your patience with me and the chat.
Atheist: and hence uniformity? well, that’s another presupposition
Chris: I actually derive it from metaphysical and epistemological givens of the Christian worldview.
And you wouldn’t be able to presuppose it in your view, since a belief, in order to be rationally held, has to have evidence.
Chris: Thanks for the conversation.