Tim asked:
What is the earliest time when you achieve the state of having an identity? Not legally, but physically. At what point is the earliest which you can become something, inadvertently die, and then at this point you will never experience life?
Answer by Craig Skinner
Good question.
It depends whether you think ‘you’ are essentially a human animal (animalism), essentially a person (the psychological connectedness view), or essentially a disembodied soul.
If you think you are essentially a human animal (and hence were once an embryo, and will still be you if you suffer severe brain damage and enter a persistent vegetative state (PVS)), then the earliest time you were you is when the fertilized ovum that became you was beyond the point where it could give rise to two humans (by dividing to form identical twins). Up to 2 weeks after fertilization an embryo can do this (in 99% of cases the split occurs by day 8), and so can’t be said to be one particular human being. So the individual human animal achieves identity when a 10-14 day old blastocyst. And, of course, inadvertent death at this point or for some weeks after (natural abortion) is commonplace. So much so that you might expect the anti-abortion lobby to press for massive research funding to deal with this, the biggest killer of human life on the planet, but they don’t, rather suggesting that they don’t really think embryos are people.
If you think you are essentially a person (psychological connectedness required), then you begin when psychological connectedness begins and end when it ends. Thus “you” were never an embryo (it lacks any psychology), and the human animal in the PVS that you become is not you (likewise lacks psychological connectedness with earlier states). In short, a human animal spends most of its life as you, excluding the earliest times when the foetus wasn’t a person (and so wasn’t you), and, sadly, in some cases, later times when the human is in a PVS and is again no longer a person.
On this latter view of your identity, you begin when psychological connexion with later conscious states kicks in. Most people would say this is sometime after birth. Some (most notoriously Peter Singer) would say babies are not persons, and can be treated like embryos. Few of us remember anything about our first two years of life (although our mums and dads often tell us about it) so you could say that you begin when the baby that became you was two years old.
If you think you are essentially a disembodied soul (the wording of your question suggests otherwise), then you begin when God makes the soul. Some think God has a supply of souls ready to allocate at fertilization, or more plausibly after 2 weeks of embryonic life (or else identical twins would share the same soul), or creates a soul at the time of allocation. So you can either exist before birth (a la Platonic view of our knowledge as recollection) or begin at the same point as described for the animalism view, depending on your religious view.
Human identity is hugely important from the legal, medical and ethical viewpoints, so be aware that discussants often confuse or equivocate between the different views of identity. For example antiabortionists are inclined to say embryos are persons, as such deserving of protection, but in view of the implausibility of a fertilized egg or blastocyst having a mental life, may switch (if religious) to the view that they have souls, or (if not) to the view that human life is sacred, ignoring the carnage of natural abortion and the legal ending of brain-dead human life.
Further confusion is added by those arguing that whilst an embryo is not a person (I agree), it is a potential person (I agree that it is a potential person, potential miscarriage, potential stillbirth and potential anencephalic birth: what it isn’t is an actual person, although it is an actual human being).
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