Science can prove a lot of things about the process of human reproduction, like what happens when a sperm and egg meet, how the newly formed zygote behaves after that point, when it implants in a woman's uterus, and so on. But the one thing science cannot "prove" is at which point in this process life actually begins--because, by definition, that is a subjective judgment based as much on moral and religious beliefs as on observable scientific facts.
Chon ends his article by saying, "And they (the doctors) are entitled to their opinion. But they should be clear that it's just that--an opinion--rather than objective scientific fact."
So let's get this straight, science can prove a "lot of things" but the definition of when the biological life of a human organism begins is an "opinion" and a "subjective judgement" based on "moral and religious beliefs?"
Sorry Jonathon. The question of when the biological life of an organism begins needs to be answered by biology not morality. Morality, religion and philosophy can help us answer whether this organism has value but they can't tell us whether it is a living organism or not.
Second, if we don't really know when life begins (since it's a "subjective" "opinion") then how do I know that a newborn or toddler or adolescent or a New Republic writer is alive?
If someone asserted that Jonathon Chon killed a living human being by putting a piece of paper through the shredder, how do you think he would respond? Would he say, "That's just your subjective judgement. My subjective judgement holds that a piece of paper isn't a living human being."? Probably not, right? Instead, if he was forced to take the accusation seriously, he would probably use biological facts to show that 1.) paper isn't human and 2.) paper isn't alive.
Why didn't he do that here? That's right. He couldn't.
Why didn't he cite standard embryology textbooks asserting that when an individual human life beings is a subjective religious belief? That's right. He couldn't.
Some pro-choicers have a difficult time dealing with the inconvenient facts of science and instead of recognizing the reality that the unborn are living human beings and then arguing from there, they instead hide behind this diminutive curtain of relativism where biological facts are treated as mere opinion.