What most people think is true of baldness they cannot really explain or defend. I think it is the same with abortion.
Unless you take extreme positions on baldness, yours is an inexplicable one. Or, at least, it defies easy explanation.
If a man loses one hair, he's not yet bald. Yet if he has only one hair left, most people would agree that he is bald. Where in the process from one hair gone to one hair left does a man become bald? Most of us have some sense of it, but our definitions would likely vary and never be precise or easy to explain.
If a sperm and egg come together, do they instantly deserve all the rights of a human life? Or in the minute before birth, can that baby be treated like a sperm and egg and be easily discarded? Most people would say no and no. But of course, that leaves the majority of Americans with inexplicable positions on abortion left to make a seemingly arbitrary decision about when the line between disposable zygote and precious baby should be drawn.
And yet this is one of those instances in which what is hard to explain seems to make more sense.