My first thought was that society would benefit most if the general population better understood the scientific method, and if the general population better understood that religion relies upon faith, and is beyond science. Because there is no test that, even in principle, would cause a religious person to discard the notion of God, this means that religion is separate from science - in which hypotheses can be discarded in the face of scientific tests.

Upon reflection, however, I will choose something more concrete. In the future, stem-cell research will become more common, and will help us to evolve and to keep healthy - despite the policies of people like US president George W Bush, who prevented the federal funding of research to create stem-cell lines. I urge our leadership and the public to keep an open mind and foster a liberal attitude, with respect to a woman's option of having an abortion, and with respect to embryonic stem-cell research.

The notion that an embryo, or a fertilised egg, should be considered human is certainly open for debate. As reported in Science magazine, 'zygotic personhood' - the idea that a fertilised egg is a person - is a recent concept. Before 1869, for example, the Catholic church believed that the embryo was not a person until it was 40 days old, at which time the soul entered. Aristotle also presumed this 40-day threshold.

If the early embryo was soulless, then perhaps early abortion was not murder. Pope Innocent III determined, in 1211, that the time of ensoulment was anywhere from three to four months. In Jewish law, the fetus becomes a full-fledged human being when its head exits the womb. According to the Talmud, before the embryo is 40 days old, it is 'maya b'alma' or 'mere water'.

If we truly believed that a zygote was a person, then we would incarcerate women who use the contraceptive Pill, because this sometimes prevents the implantation of a fertilised egg. We do not wish to jail such women, or their physicians, hence we do not actually believe that a zygote is a person.

Birth control methods have prevented the production of millions of unwanted children, and have lessened widespread suffering. If people can overcome the fallacy of zygotic personhood then presidents can ease restrictions upon human embryonic stem-cell research, which has the potential to help people with Parkinson's disease and diabetes. Although non-embryonic stem cells, such as multipotent adult progenitor cells, may eventually be suitable substitutes for embryonic cells, we should not restrict stem-cell research now. Similarly, those who hope to ban cloning, because it may entail the discarding of zygotes, might rethink their position.

With women gaining more control over their reproductive fate, society has changed. Reliable birth control became as easy as taking a pill, which - along with education - is one of the greatest factors in helping women to achieve equality with men. Athough religious people may debate whether a fertilised egg, or zygote, should be accorded the same rights as a child - and therefore, whether destruction of the zygote should lead to imprisonment - no one debates that the Pill, and other methods of birth control, have decreased the suffering of fully formed, multicellular humans.

Very few people today believe in gametic personhood, the idea that sperm and eggs are people; or in homuncular personhood, the eighteenth-century idea that the entire human organism - the homunculus - is contained in the spermatozoa. Similarly, the notion of zygotic personhood may someday fade.

Clifford Pickover is author of books including Sex, Drugs, Einstein and Elves: Sushi, Psychedelics, Parallel Universes and the Quest for Transcendence (buy this book from Amazon (USA)), and A Passion for Mathematics: Numbers, Puzzles, Madness, Religion and the Quest for Reality (buy this book from Amazon (UK) or Amazon (USA)). See his website.