> I can't see anyway to consider that "good".
Of course it's good. If the frog could engage in abstract reasoning, he would have no reason to care about evolution or reproductive success.
If you just substitute "human" for "frog", you can see it's true for us, too (and we can reason). You'd be badly mistaken to define good and bad by "repdroductive success." That would be committing the naturalistic fallacy.
The reason taking some kind of pleasure-drug goes against people's normal moral sentiments is because it's too much of a false hypothetical. A true pleasure drug would be very dangerous, so we wouldn't take it.
> Now consider the wide range of what humans consider pleasurable. A community of sadist may derive great pleasure from tormenting an animal. In your argument, that makes it "good"
That is not actaually an implication of my argument, because sadism is not going to lead to long-term, fulfilling happiness. There is no deductive argument I can offer for that; you just have to look at and observe human nature honestly to see it.
> Is your argument ignoring people who derive pleasure from harmful things because you don't know anyone like that"? That seems a bit of a hole in your point of view.
No, it's a turn of phrase. But I am making the point that the way I know what I know is by observing human beings. It is empirical.
Anyway, I didn't write my long comment (above) for you---I wrote it for someone who was asking a genuine question. Somebody who is instead just trying to defeat my argument can always go one step more fundamental until we cover all of ethics, epistemology, and metaphysics. I'm not going to do that on hacker news. You can go to philosophy books for that. People can certainly learn things from some of my comments, if they want to learn, but my comments are not very useful for debating/winning arguments, which is not what I am into. That said, I am happy to chat.
To put it more simply, yes, there are holes in my argument---because I am not going to wrie a philosophical treatise on here. You can fill the holes in yourself by thinking; it's left as an exercise for the reader. (However, there are not holes in the sense of fallacies or contradictions; that is not what I mean by "holes" here.)