Update. The question has apparently been reverted to its previous state by
Lennart Regebro, apparently because he felt that I substantially expanded the question. I feel that my points below apply to the question as it originally stood, in any case.
I recently encountered the question, "Is it possible to scientifically determine good and evil?", and I must say that it is not clear that it deserved to be closed. I would like to ask if there are deeper reasons for its closure than is evident from the postings on the question itself.
There are only three arguments presented in the comments for why the question should be closed. I am puzzled by them, and will present counter-arguments to each.
As asked the question seems to set up a definition of evil as that which results in relatively bad results for sentient beings. It's a circular definition on its face. [...] I stopped reading the article at this point: "[The Catholic Church] did not excommunicate a single member of the Third Reich for committing genocide. (It excommunicated Joseph Goebbels, but this was for the high crime of marrying a Protestant.)" It seems willfully ignorant of it's subject. (For reference, Germany has been outside of Catholic authority since the Reformation.)`
For what it's worth, it's not clear how his argument is ignorant. (The behaviour of Catholics of all nationalities represent a significant concern for the Roman Catholic Church, and at the time some of them were German.) But Harris' remarks on specific religions are more or less beside the point even of his own essay; they're there only to convince the reader that determining what is moral is a question one may ask.
More importantly, the definition isn't (obviously) circular; if "good" is being defined as "well-being", then the usage of "bad" being "bad for the thriving of the person" is just (a) a typical instance of overloading of the word 'bad', arising from (b) using it as the logical complement of two things generally regarded as "good". The fact that well-being is unthinkingly regarded as "good" is in fact Harris' main observation; and the question of the OP is asking whether there is any problem either in proposing the identification of the two concepts, or in any programme to then empirically discover the consequent scope of "goodness".
In any case, it's clear that the moral metric being proposed is actually a question of "well being"; I do not see how there is any circularity here, any more than there is in talking about using the phrase "public good" to refer colloquially to the stability of society and happiness of its members.
-1 and vote to close, off topic and argumentative [...] It definitely seemed less than a constructive way to approach the general question of criticism of Harris/the Brights/etc.
Sam Harris may be argumentative, but I genuinely don't see how the question itself was. (One may object to Sam Harris or the Brights in themselves, but the mere fact that Sam Harris is one of the people arguing for the possibility of an objective notion of morality cannot be a valid argument against the question itself; that's a fallacy of association).
Furthermore, I don't see how it fails to be a constructive way to approach the question of (one of the notions being proposed by) Sam Harris or the Brights. There may be a problem in that it is difficult to refer to a text of Harris without running into a bit of antireligious polemic, but surely it is possible to set aside the parts of his arguments which are obviously irrelevant (except inasmuch as he is trying to convince his audience that one should be sceptical of would-be moral authorities) to address the question itself.
I cannot comment on how this question differs from the linked ones, as the linked ones have been deleted. However, as someone else noted in the comments, this question is not one about "what the difference is between good and evil"; it is whether there is a problem with a particular proposal to define "good" and "evil" in a particular way which in principle would admit empirical determination.
If the question of whether or not morality can have an intersection with empiricism even in principle, if you grant certain utilitarian-aligned premises is not on topic for philosophy, I'm not entirely sure what is. And once again, I do not see how the question was not constructive.
In summary, the reasons why the question were closed look very convincincly like the problems that certain participants had with Sam Harris' writings, rather than the actual question. While the question was informed somewhat by Harris' writings — in the same way that a question about existentialism could concievably make reference to some of Nietsche's writings which were subsequently falsified by his sister — I could detect no "unconstructive" or "argumentative" elements in the question itself.
I have attempted to revise the question, but in truth, all I did was to hilight the themes which were already present in the question, and add a disclaimer that Sam Harris' criticism against religion is not the subject of discussion (as indeed it never seemed to be, except in the eyes of some of the commenters). Perhaps the OP wrote some comments which have been deleted, but I came across the question as it originally stood, and saw nothing of the sort in the question.
So I ask: is there a reason why this question should still be closed?