Is human nature good, evil, or whatnot? I don't pretend to answer that in this post. My point is just to try to come to an understanding of what the question means.
First, though, we need a sense of what "good" means. A solid definition is not necessary, so long as there is some content to the word. It is not good for a person to starve to death. It is good for a person to have enough to eat. Let's start from such examples before getting into controversial moral topics.1
Next, what is nature? Nature is what happens always or for the most part. What people tend to do on a systematic level is what human nature is for the species. It does not seem necessary to say that nature is fixed given this definition. A snapshot of human beings from 10,000 BCE to 0 BCE would probably give a different view of human nature than than between 600 BCE and 10,000 CE.2
So, the first thing that the question could mean is: would human nature be good for the individual? That is, if one goes around doing typical human things, does this tend to lead to what is good for specific people? Another way of putting it perhaps: does living an average human life tend to be satisfying? Of course, one can find stories to fit both sides, so the question is asking what holds for the most part (or even if there is a "most part"). If human nature is good in this sense, then one does not have to adjust one's basic instincts in order to live a good life.
Another possible meaning would be whether human nature is good for society. If people live just according to how human beings tend to act, how does this affect others? Do people left to their own devices tend to make society work (such as free-market economic models posit) or do they actually land people in a position which may be worse for everyone involved (like in the prisoner's dilemma)? Of course, the answer doesn't have to be reducible to just these two positions.
Finally, the question could be asking whether pursuing one's own good leads to the good of the society or is contrary to it. If the two are contrary, then anything one does for oneself is selfish, and anything done for others is altruistic (think Ayn Rand, who would argue that one should therefore take the selfish option). However, if the two are aligned, then doing what is good for oneself automatically leads to doing what is good for society (much Confucian philosophy, in particular Mencius/Mengzi, would agree with this).
These questions are all to an extent independent. Human nature might procure what is good for the individual but what is bad for society; if people live according to their basic desires without cultivating them beyond the norm, they might gain a satsifying life for themselves while hurting others.3 And there is a difference between saying that human nature leads to what is good for society, and that the individual good leads to what is good for society; it may be that human nature is destructive to the individual, but that what is truly fulfilling and satisfying to the individual would actually be good for everyone.
1 Of course, what "good" is depends on what a human being is. If one takes a human being as something which we treat for practical purposes as having free will, and anything constrained by the natural world is determined, then the good of a human being does not have to do with the natural world; this would be Kant's view, in which what is morally right is determined by reason alone as the only law which makes the will autonomous. So we can still come to conflicting views of what "good" is if our views on the essence of human beings conflict. But this does not mean that the term "good" is rendered meaningless; you still understood what it meant in this discussion.Top
2 What is the relation between "nature" and "nurture" on this view? That is a complicated question. One the one hand, there are ways in which society teaches individuals to put aside many of their basic instincts to take part in the larger group. So it might seem that society always leads people to live contrary to human nature. However, society regularly teaches people to maintain a certain level of decency towards each other, and people are regularly receptive of this. Even in dysfunctional societies, most people are not serial killers. This would mean that a good amount of "nurture" is part of nature, both in the giving and the receiving.Top
3 Though, given that we are talking about nature, what happens always or for the most part, one might see that these questions are interrelated. It cannot be the case that most people live a good life for themselves, while simultaneously preventing society at large (that is, most people) from living a good life. But the two questions are separate. One might also speak of potentials: human nature gives one the potential to become a selfish warlord who lives a good life at the expense of others.Top