Trite and ineffective line of reasoning. Do you think that a soul inhabits an embryo before implantation, before self-awareness, at conception? If so, what harm comes to the soul by the embryo simply not implanting, the cells dying a natural death? The soul moves on, the human doesn't suffer.
What is your position on what is a soul, how it comes into being, how it leaves the body, etc. And where are you getting this info? Rome?
I don't base by thoughts on birth control or fertility medicine on when a soul inhabits a body. I find it amusing that one of the people who really liked and popularized this soul argument was Bill Clinton when justifying his veto of the partial-birth abortion ban.
It's called natural law.
The symptom of the presence of the soul is life: growth, etc. The rationale that an embryo isn't worthy of living can be applied to any unborn baby, and, according to "ethicists" like Professor Peter Singer, to born children as well, if they don't achieve certain standards. And also old people, and sick people. Some of them might be considered to not be "self aware", and certainly have no bright future ahead.
So you're saying that there must be self-awareness to warrant not being killed? How much self-awareness? A lot of newborns aren't very self-aware either. People argued that Terri Schiavo wasn't self-aware. Should she have been killed, or should she have been allowed to live?
I get my information from three places:
1. Common sense
2. Vedas
3. Bible
And the Golden Rule, which is extant in one form or another in every religion in the world. Just as you like being allowed to live, let others live. Just as you don't like being murdered, don't murder anyone.
This reminds me of one of the letter writing exercises I found on pro-abort web pages some years back.
The aborting mother was to write a letter to the soul of her aborted human fetus, explaining why it was better that the fetus was killed. The non-mother was to assure the fetus that they would meet someday in heaven.*
The pro-aborts certainly lack logic.
They'll say the fetus has a soul when it suits their argument and then turn around and say the fetus has no human soul.
*I can imagine the hospital personnel who killed the New Orleans patients are writing letters to their dead victims right now.