Science cannot defeat mortality.
I reject this premise because the end of aging is already in sight. If you're interested, I would recommend Ben Bova's Immortality: How Science Is Extending Your Life Span and Changing the World or Michael Fumento's BioEvolution: How Biotechnology Is Changing Our World or Michael West's The Immortal Cell: One Scientist's Quest to Solve the Mystery of Human Aging or Stephen Hall's Merchants of Immortality: Chasing the Dream of Human Life Extension or Jay Olshansky's The Quest for Immortality: Science at the Frontiers of Aging or last but not least The Scientific Conquest Of Death from the Immortality Institute. While you're at it, that last link to their website is a good place to surf over to, and check out the Foresight Institute or the Extropy Institute as well.
As Ben Bova opens his text: "The first immortal human beings are probably living among us today. You might be one of them." In any case, the end of aging is already in sight, and progress in that direction will inexorably accelerate (notwithstanding interference from Luddites such as the president's 'bioethics czar' - the contemptible Leon Kass). Even if science does not defeat mortality, it will not be because it cannot do so, because the means are already well in sight, even if we lack the expertise to implement them.
It cannot "cure" death.
Science can already "cure" death; it happens in hospitals every day across America and around the world. And with every passing year science is getting better and better able to "cure" more advanced or complex stages of death. In fact, many deaths that go 'uncured' these days are not because they cannot be 'cured' but rather because the underlying reasons for the death cannot (yet) be repaired.
And it cannot make man "good."
This depends on whatever it is that one defines as "good" or "evil" (presumably, by contrast). But, whatever it is, there is little doubt that it can be controlled by genetic manipulation (whether one should do so is another matter altogether). If science were to seek to "make man 'good'" it would only be a matter of identifying precisely what neural structures permit the enactment of a given 'evil'; what genes control the given structure; and then its genetic modification.
***********************************
So, that is why I reject all three alleged "facts" as framed above. Oh, and one thing I can tell you for certain is that religion has achieved none of those.
Moreover, on personal knowledge I aver that God not only can but has accomplished all of these - albeit, not for everyone.
The snafu in the extension of the length and quality of life argument is (as always) the geometry of space/time and the physical laws:
Immortality cannot be achieved as a corporeal "in" space/time because space/time is finite (at least in most cosmologies). The second law of thermodynamics will eventually bring about complete physical entropy in this universe, a ripping or a big crunch. To avoid this end, science would have to stop physical entropy throughout the cosmos.
Also, objective truth such as "what is good?" cannot be determined "in" space/time because (a) man's vision and mind are limited by four dimensions, (b) man does not possess retrocognition, precognition or remote sensing, (c) man cannot share another man's being - physical senses, qualia and intelligence. Such objective truth can only be received as a revelation from God who is "beyond" space/time and also transcends space/time.
As a last point, it is curious that science is seeking "immortality" when it has yet to embrace a rigorous definition for "what is life v non-life/death in nature".