It is often held, by admirers of modern science (which took off around about the 15th century) that if human beings are parts of nature, there can be no room for morality in their lives. They are then simply complicated machines working as they must, with no possibility that they can make choices, which is an essential part of morality. Science and morality are, then, often juxtaposed.
But there are several problems with this. For one, nature is bountiful in its variety; so simply because other parts of it are mostly determined to move as they must, it doesn't follow that all parts do. Just as there are living things that swim, as well as some that fly or simply slither about, there could also be some that are dumb beasts and others that think, reason and make choices. Nothing unnatural about that at all. And once something uses higher reasoning to get on in its life, choices are just around the corner.
Also, those who insist that we are all fully determined to do as we do tend, paradoxically, to be very moralistic about insisting that this is how everyone ought to think about us. In effect they believe, "No one ought to believe that people have free will, that they can make genuine choices in their lives; they ought to be thought of as complex machines." However, without the capacity to choose, such admonitions are meaningless.
Without the capacity to choose, without free will, our thinking is also purely determined and so if we do believe in free will, we then must believe in it. Yet why then get annoyed with us for failing to heed the advice of those who deny our capacity to choose?
Not only that, innumerable scientific minded folks make moral declarations galore. Blaming and praising are part of this exercise and champions of the scientific way quite often blame and praise. They blame those who reject their imperialism about how nature behaves and they praise those who share it. They often outright denounce those who think they shouldn't be given extensive government funding for their work.
In the recent discussions by the likes of Richard Dawkins, Sam Harris, and Christopher Hitchens, the group called "the new atheists," all kinds of blaming is in evidence when others who don't embrace Darwinian evolution or do embrace creationism are being talked about. These people, these champions of science insist, others aren't doing the right thing, namely, accepting Darwin as correct about how the world works. (Not even all of these scientifically minded people deny free will, by the way.)
The point I am making isn't about whether such blaming or praising is correct but that it doesn't square with the belief that we are all determined to be the way we are, that we all work like machines.
In more recent discussions of human choice some scientists have suggested that there might be room for it now that Newtonian physics has been superseded by contemporary, post-Heisenbergian quantum physics, the kind that leaves some room for uncertainty (at least at the subatomic level of existence) and thus might allow that not everything is fully determined to happen one and only one way. (Not that the features of quantum physics that they rely on for this necessarily support anything like human freedom of choice!) In particular the late Karl Popper and John Eccles had thought that the new physics allows for free will (presented in their book The Self and Its Brain [Springer Verlag, 1977]).
So while there is wide consensus among champions of the natural sciences about whether human beings have a moral nature – can reasonably be held responsible for the conduct they choose to embark upon – some dissidents do exist who think that, yes indeed, we are moral agents; it's a distinguishing aspect of our nature but still quite natural. And certainly quite a few scientists and their champions act like we all did have free will, when, for instance, they blame those who refuse to accept their ideas about evolution. As already mentioned, blaming someone implies they have the freedom to choose how they think and act.
Of course, the world of human beings is filled with moral elements. Personal, social, political and international affairs are all replete with moral concerns, with how we ought to and ought not to think and act. And since this is also in evidence among scientists, it is probably the right way to think about us.