What does it make sense to believe without evidence?

Let me start with a little background on why I’m asking the question:

My fiancee believes that the Christian Bible is entirely true. She acknowledges that some things in it may be metaphor, and translation may have altered the meaning of certain passages, but she feels that the original text at least was divinely inspired, and that every sentence of it contained truth. She can explain to me why she believes this (in terms like “it’s what I was raised to believe”) but can’t really provide any evidence to support this belief.

Even though I’m not really a person of religious faith, I recognize that there are some things I believe without evidence. For instance, I believe that if something has usually proven true in the past, this indicates that it will probably continue to prove true. However, the only reason I can give for believing that statement is that it has usually proven true in the past. Obviously, this is quite circular.

I also believe that the input I receive from my senses corresponds in some way to physical reality. I have absolutely no way of proving this (since any way I could try to prove it would necessarily rely on my senses). Yet I still believe it to be true, despite the lack of evidence. Moreover, I’d say almost everyone believes this, or at least they behave as if they do, even if intellectually they acknowledge other possibilities.

So, my question is, are all these beliefs equally reasonable? Is there any sort of rule we ought to follow in deciding what is reasonable to believe without evidence? Or is every belief equally reasonable?

At a certain point, you must rely on faith for everything. I don’t mean to take an extreme position such as Bishop Berkeley’s argument that reality may not exist since all evidence comes from the senses (a horrible oversimplification), but psychological tests have shown that our perception of reality is often an odds with an objective reality but we have faith that our perceptions are real - otherwise we couldn’t function.

In terms of religion, I would argue that not only is trying to prove fundamental religious tenets as true or false a losing proposition, but moreover faith (accepting without proof) is fundamental in Judeo/Christian/Islamic religions. But in terms of the writings, they are written by humans (possibly inspired, possibly not) thus fallible or contain relative moral instruction for specific groups of people. If your girlfriend does not believe this, then the next time she walks out the door without a hat, call her a common street whore. When you regain consiousness, tell her to read Corinthians.

In both the cases you give, you are both believing on evidence and testing your beliefs. By an informal sort of induction, things that have been the case continue to be the case. Yet I’m sure you would not be too shocked if at times they we were not. Each day we wake up, aware that someday we will not.

Though it is true that you cannot prove the evidence of your senses is correct, you act as if it were. If suddenly this causes a problem (like you walk into a wall that you cannot see) you would correct it.

John Maynard Keynes (yes, the economics guy) wrote his first book on just this subject, and concluded that each time your belief is confirmed it adds to the probability that it is true. It might never reach 100%, certainty, but in most cases it gets pretty close.

So you’re in good shape. Your fiancee on the other hand …

And as you wrote later in the post, the more times you act on the evidence of your senses and it turns out to be correct the more you can and do trust the reliability of you senses.

As British mathematician William Clifford said - Truth is not that which can be contemplated without error. It is that which may be acted upon without fear.

As to the truth of the Bible. I think there is quite a bit of advice in the New Testament that wouldn’t be wise to act upon. Using Clifford’s test it wouldn’t be “true.” Turning the other cheek to a sadist for example. Of course Jesus, as portrayed in the Testament, was giving advice that was valid in a world that was going to end before “this generation has passed away.” So maybe turning the other cheek to a sadist in this world would be valuable in a future world, if such existed. And if you are going to believe in another, future world you must do it without evidence.

We must all select some axiom from which to start our reasoning. No axiom is self-selecting. Even “reasoning” itself is not an absolute: it is a protocol by which we combine statements to yield a conclusion, rather like the final output level of an arrangement of AND or NOR gates, and for 14 billion years there simply was no “reasoning” going on at all, nor any “truth” since that is itself an output of an apparatus following such a protocol (‘truth’ perhaps being physically characterisable as a high correlation between combinations of memories and combinations of sensory inputs).

What about the above one?

You can choose to consider it false, or irrelevant, or whatever. The output of my mind is that statements are the outputs of minds. Your mind might output something different.

But how can I conclude my senses gave me correct information without assuming my senses are correct? Saying, “I trust the information given to me by my senses because my senses consistently confirm it” seems uncomfortably circular.

Plus the whole thing is inductive reasoning, which has essentially the same problem: my conclusion that inductive reasoning works is based on inductive reasoning.

Don’t get me wrong: I’d like this to be different than “I believe the Bible is the true word of God because the Bible says so,” but I’m having trouble identifying the difference. The only reason I can see that the statement about the Bible seems less reasonable is because I personally don’t have the same faith in the claim “the Bible is true” as I do in the claim “my senses are giving me a (generally) accurate picture of reality.”

OK, but let’s say I had decided to do the opposite. Suppose I decided to assume my senses were incorrect. For instance, I might assume I’m living in some Matrix-like simulation, and my senses don’t have anything to do with my reality. If the Matrix programers did their job well, I’d never be able to see anything to suggest my senses didn’t correspond to reality – so the fact that they seem to correspond to reality would be just what I expect, and would do nothing to cast doubt on my theory that my senses were lying to me. So is this an equally rational belief?

I think the key difference here is that religious faith holds clinging to the belief in and of itself to be a virtue, as well as resisting logical arguments and evidence that contradict it. Otherwise there is no fundamental difference between the *initial * belief that your girlfriend has and belief in the validity of ones senses. But your girlfriend’s belief basically says that as time goes on I will find a way to believe this statement no matter what (or conversely that there is no evidence that could invalidate my belief) - with is what distinguishes religious faith from belief in reason.

There isn’t one. One initial attack would be that you know that people can communicate false information, via speech or text or other modalities. So, communication by itself is not a sign of truth. I can and will type: This sentence is in French. Which is false. But what does ‘false’ mean? It is inconsistent with what it means to write in French. And in your epistemology, it is near certain that the earlier sentence is false rather than the fact that your knowledge of French is incorrect or lacking. But ultimately, the problems of uncertainty (possibly incomplete knowledge) and induction precludes you from being absolutely sure that the sentence is false. The Bible could be true, even if someone could prove in an agreed upon consensual logical schema that it being true is equivalent to 1+1=3. From this, the question becomes ‘how we we realize and justify that the truth could be anything?’. One possible answers: We have some sort of a priori knowledge and intuition. Now, if that is true, it can’t be proven by its very nature, but it’s not the same as faith.

A little simplistic isn’t it? Don’t we act on things that we percieve to be true even when we’re very afraid?

We all make judgement calls on what we percieve is true and valuble to us. There are things we have evidence for that can be examined by those around us and we can use their input as a check against our own judgement. In some cases people are so influenced by those around them that accept the common perception of “truth” without checking for themselves.

I think religious tradition and myth are like that. There is evidence to examine about the Bible if someone has the desire to look at it honestly. Religious tradition holds a different place in our hearts and minds than other traditons and are especially hard to let go of.

The matrix analogy may be a good one to religious belief. Neo was able to operate within the matrix even after he discovered what it was. Is it *rational * to believe that what you percieve within the matrix is reality when that’s all the evidence you percieve? I think so. If you had some internal experience that made you suspect that the matrix was not all of reality would it be rational to pursue that experience and seek further experiences to try and understand the nature of what lay outside the matrix? I think so.
Of course it gets complicated when you have a few thousand groups telling you their version of what lay beyond the matrix is the correct one, and others telling you that the matrix all we have evidence for so don’t waste your time considering anything else. We must each decide for ourselves.

Well, there’s one thing that’s reasonable to believe without evidence.
Namely, that you exist. It’s possible, after all, that you (By which I mean the individual reading this sentence, not the general audience) are a brain in a jar, or a computer program, or someone else’s dream, and you’re not actually reading this sentence.

It’s stupid, but you can’t prove it false. It’s also handy to accept that other people exist. They may fall under the same category, but… eh. Can’t prove it true, either.

After that, anything you experience directly has a varying chance of being true, depending on the amount of corroborating data you have.

Things taken on faith? Well, anything that you have no evidence on, and can have no evidence on, such as the existance of an afterlife? That can certainly be a position you take on faith. In fact, you have to. God not wanting you to eat cheese and meat together fits there, too. Or no fish on fridays.

Things taken on faith that do not directly affect the world around you can be taken on faith, until you expose evidence that suggests they are not true. Then, they should be re-examined, but it’s not really that necessary if you don’t want to. You don’t need them in your daily life. Evolution and the historical existance of Christ fit here. For the typical office worker, even if the evolution of disease resistant strains of bacteria does affect them? Doesn’t really matter, because it’s way outside their hands. Global warming, too. And for many people, the fact that the world is round isn’t that important, either. Not for them to continue on their lives.

Things taken on faith that directly contradict hard evidence they see daily. “I can walk through walls.” “I can fly, if I study yoga hard enough.” “Any sickness or disease can be cured by prayer.”

Those are just messed up, yo. And really should be re-examined before they get you… or someone else… hurt. I mean, even if all y’all are imaginary, I don’t want to have to pretend you guys are in pain, either. :slight_smile:

No, I don’t believe everyone’s imaginary. It’s just a good way to keep reminding me to re-examine my preconceptions.

I don’t think that we are assuming the senses are correct. We are measuring the result of trusting our senses in each case by the outcome of our actions. Suppose the outcome of our actions based on sense experience results in no injury to us, or our property, or society in case after case. Then when we have that same sense experience again we can confidently expect that we and society will be safe if we take the same action. And vice versa of course.

I think that you are taking Clifford’s “fear” to mean only physical fear. I think what is meant is that we can act without worrying that our actions will produce an undesirable outcome although not necessarily a physically dangerous one.

I don’t follow you here.

No I’m not thinking of only physical fear. What I’m suggesting is that our perception of the truth may ask us to do things that are scary without knowing the outcome. Confrontations of various kinds can be examples.

I’m reminded of a discussion of faith I read years ago. There are three kinds of faith; faith with evidence, faith without evidence, and faith in spite of evidence.

The first, faith with evidence, the author referred to as “The faith of Goddard”. Goddard didn’t have any examples of space travel via rockets - but the laws of physics told him it was possible, and they have a long history of being right. Another exapmple would be trusting that the sun will rise in the east and set it the west.

The second, faith without evidence, is more problematic. The third, faith in spite of evidence, is outright dangerous.

So, what the real issue is, here, is unexamined faith?

Sounds like it to me, Bosda.
Who was it that said, “The unexamined life is not worth living.”?
Ah, yes, Socrates.

Der, sure, but it’s possible to have evidence and not have it matter to your personal life. I may think someone who believes that every sunday night, California flies off to Guam for the weekend, is nuts… but if they live in Jersey, it’s not going to change their lives any.

I think a lot of faith is like that. Once examined, it becomes mildly obvious it’s a bit off… but until you examine it… you don’t notice.

Of course, once examined, some people accept reality, and some people try to change reality to fit their faith. Those are the ones to watch out for.