Madam, - Zygote time again (Letters July 6th). The idea that because we don't know at what stage exactly a developing embryo becomes a person, we must therefore go back the whole way and extend full rights to a zygote, seems unsound, because, according to this logic, before we know it, a zygote is a person!
What has happened here is that an implicit definition has been derived from the absence of any agreed definition in the first place.
It is often difficult to get the idea across that the proposition, "Human life begins at conception", is not a biological or a biochemical thesis; such theses can be falsified in laboratories. What procedure would need to be carried out to falsify the assertion that a zygote is a human person?
For those who believe in ensoulment, in his book The Soul, an InquiryFr Francis Selman says: "Even if we cannot know that the human soul is infused at conception, this still does not permit us to destroy zygotes up to the time when we think that they become human beings, because we should give the benefit of the doubt to something that might be a human being". (pages 96,97, emphasis his).
We cannot know, and some may not choose to give the benefit of the doubt, but that is for them to decide as best they can. - Yours, etc,
Dr JAMES MURPHY, The Pigeons, Athlone, Co Westmeath.