Good and Evil

[Pyrrho]

The valuing of health is certainly not a matter of science.  That people generally do value health is a matter of fact, but that they ought to so desire it is something quite different from a mere poll of what people value.

According to Hume, the notion that someone could choose poorly negates the possibility of anyone making a valid objective judgment about what is best.

You need to explain that a bit.  What, exactly, do you mean by "objective?"  That someone does not agree is not a problem for Hume.  Indeed, his list of "monkish virtues," which many religious people claim to cherish, Hume regards as vices.  I already quoted that earlier in this thread:

http://atheistforums.org/thread-33164-po...#pid934918

But that cannot be because even scientific inquiry is impossible without making value judgments, like determining that a pure sample of something is better to study than an adulterated sample.  Anyone can see that the researcher choosing a sample is making an objective value judgment.

There are a couple of things to be said about that.  First, the fact that an experiment with an adulterated sample will not necessarily tell one what would happen with the same experiment with a pure sample is not a value judgement.

Now, the desire to run the test is a motivator to get it right, but the desire to run the test is not a part of the test.

Furthermore, the motivation to do anything always involves emotions.  That was something Hume noted.  So scientific enquiry is impossible without emotions, as one would never have the motive to do such a thing without emotions.  But this is not involving "an objective value judgement."

Adults tell children that they shouldn’t play in the street because they could get run over. Imagine a smart kid saying, “The fact that I could get run over if I don’t watch out does not mean I shouldn’t play in the street.”

The smart kid probably does not want to get run over, just as most children don't want to get run over.  And the smart kid, being smart, will know that his mother is right about the fact that he might get run over if he plays in the street.

No moral judgement has to be made at all in this kind of case.  A pragmatic "ought" is all that is necessary in such cases (or what Kant called a "hypothetical imperative").  If one does not want to be run over, then one ought to be careful about playing in the street.  It is about means to an end, and does not require any moral judgement at all.  The hypothetical is only relevant to those to whom the antecedent is applicable (to those who do not want to be run over).

Anyone can see that the ‘is-ought’ objection for what it is: juvenile.

I happen to think that the mainstream interpretation of Hume on 'is-ought' is wrong.  That is to say, I don't think Hume said what people claim he said.  If you want to discuss that, please start a new thread on it, and we can discuss it there.  If I don't respond there, you can either tell us of the new thread in this thread, or you can send me a PM telling me about the new thread.

Life is an essential part of being an animal.

No.  A dead animal is still an animal.  One might even be tempted to say that dying is essential to being an animal, but we should probably avoid this sort of digression, as it has no bearing on either what Hume had to say or on morality.

The act of making value judgments is a necessary part of rationality. When someone acts irrationally and unnecessarily endangers his life that means that he doesn’t value being human, not that human life is without value.

Many people feel as you do on that, but it is a feeling on your part.  Evidently, your idea of "rationality" includes more than bare reason, but also feelings.

To actually want what undermines your humanity makes you a worse instance of human. You ought to be the best person you can. That is an objective moral imperative.

First, explain what you mean by "an objective moral imperative."  Then prove your claim.