[jas3]

The blastosphere is either fully human or not fully human, unless it is a chimera.
And parents looking for perfect human children probably aren't interested in giving birth to chimera children.

Well, we can agree that a blastosphere has the potential to become a human in the same sense that an acorn can become an oak tree (but is not yet an oak tree), caviar can become a sturgeon (but is not yet a fish), and a spore can become a mushroom (but is not yet a mushroom).

A blastosphere shares characteristics of human and may contain all the information required to become a human, but it is not yet a human any more than a blueprint plus a roof shingle is a house. That doesn't mean that a blastosphere is not deserving of legal protection or that there is no moral consequence to the destruction of same, but a blastosphere is not "a" human....at least not yet, and more likely than not, not ever.

I disagree with you and expect that chimeras will become the norm this century for parents who accept the promise and perils of genetically engineering their children. Parents will eventually be given the option of having children with many genes that are either plucked from existing animal genomes (see in the infrared! hear ultrasonic frequencies! etc.) or are specifically engineered from scratch and did not previously exist. It wouldn't surprise me at all if parents identifying themselves as "goth" choose to have bioluminescent children.

Speaking of chimeras, are you familiar with the concept of fraternal twins merging to create a single human chimera, i.e. one person with two distinct cell lines? It is amazing that one's immune system permits such a situation to arise, but there are several documented cases of this happening with the adults only recognizing this condition when they type tissue for organ transplant or attepmt to identify offspring of questionable origin.

I wonder from a theological point of view what various various churches which believe a soul attaches to an ovum at conception might suggest has happened to the "extra" soul. The existance of such human chimeras strongly suggests that human souls are not attached at conception (or alternatively that some people have two souls).

jas3

[syriacus]

an acorn can become an oak tree (but is not yet an oak tree),

An acorn is a seed and has the oak tree within it.

A seed contains an embryonic plant in a resting condition, and germination is its resumption of growth.

[syriacus]

I wonder from a theological point of view what various various churches which believe a soul attaches to an ovum at conception might suggest has happened to the "extra" soul. The existance of such human chimeras strongly suggests that human souls are not attached at conception (or alternatively that some people have two souls).

I am not interested in counting souls.

Here's another way to look at the situation.

You would not feel free to destroy a building if you knew a small child was inside.

Would you feel more free to destroy that building if you thought 2 or more children might possibly be inside the building, instead of only one child?

Likewise, it doesn't really matter how many humans are in the blastula.

What really matters is that at least one human is present.