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Scea91

Just note that believing something because it has nice consequences is just logically wrong.

Formally:

1) A => B

2) I would really like B to be true, because it has some benefits.

3) Therefore A must be true.

If we are in search of truth and want to build a consistent model of the world then we just can't accept this kind of reasoning.

Also, even if A really turns out to be false, it doesn't mean that B can't be true and our world will forever be sad i.e. Even if it turns out that all people are not created equal, we can still live in just and enlightened society which treats everyone fairly.

And of course the implication between A => B may not even exist. Is it really true that if all people were created equal the society would benefit?

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First, please do not get too hung up about "all people are created equal". It's just an example in this context.

> If we are in search of truth and want to build a consistent model of the world then we just can't accept this kind of reasoning.

Yes, you can. It's called generalizing. Remember, we're not doing math here, this is ethics.

Think about all the different situations where being treated equally to someone else is a good thing. Now you generalize that into "everyone is created equal", and that turns into a justification for all these situations.

If you want to criticise the generalization into A, there is a way:

Construct some C so that

1) A => C

2) C is not beneficial

Alternatively, you can attack the implication "A => B" or you can question whether or not B is beneficial.

> Think about all the different situations where being treated equally to someone else is a good thing. Now you generalize that into "everyone is created equal", and that turns into a justification for all these situations.

The valid generalization would be "everyone should be treated equally" not "everyone is created equal" which is a totally different thing.

Good point.

EDIT: I think what you're doing here is criticising A by constructing A' and arguing that it is better (by having the same consequences while being less general). That is a good way of criticising the generalization as well.

>> If we are in search of truth and want to build a consistent model of the world then we just can't accept this kind of reasoning.

> Yes, you can. It's called generalizing. Remember, we're not doing math here, this is ethics.

To strive for a consistent set of beliefs grounded in reality is more akin to most branches of Philosophy than Mathematics as far as I am concerned, and seems particularly concerning to Ethics (e.g. you can achieve a set of beliefs of what you can consider 'good' or 'evil' ignoring all perception of reality but would the result be desirable?).

I would disagree with the generalization. Consider the following set of propositions:

1) The placebo effect predicts that believing I'll get over a bout of the flu quickly increases my chances of getting over the flu quickly

2) I believe in the placebo effect and would like to get over the flu quickly

3) Therefore, I choose to believe I will get over the flu quickly.

There is no reason besides practicality to believe proposition 3), but if propositions 1) and 2) are accepted, proposition 3) follows naturally. To my own way of thinking, some beliefs are self-justifying, but I'd be interested to hear how your worldview deals with this example.

edit: spacing

Quite an interesting counterexample. The trick is in the self-reference where the fact that you believe the premise actually affects the conclusion which most of the time is not the case.

I might consider this an edge case and include it in my worldview as an exception ;)

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