Last night, for the first time in his life, my little boy asked his mother if she grew him in her tummy. For his mother and I, it was a startling moment: we adopted him at birth and always told him so, but now, before age four, he's beginning to connect the dots. You can tell a preschooler something over and over again (and we do), but he'll only understand it in his own time and in his own way.

The process of domestic adoption in the United States is long and complicated, especially when you do it in the state of Colorado. That's where we adopted our son. It involves classes, background checks, invasive personal interviews, and in the end, you don't pick a baby: the pregnant birth mother picks you. Even if the birth mother picks you to be the parents of her child, she still has five business days after the birth of the child to change her mind. It happens about 33% of the time. It happened to us, after we'd brought the first baby home and cared for him for a day and a night.

On our second go-round, we were successfully matched with a birth mother and placed with a baby who became our son.

Before making the decision to adopt, I had prided myself on being pro-choice: if a woman wants to get an abortion, who was I to say anything about it? Doesn't personal freedom mean being able to make such important personal choices about one's own body? Ultimately, it was an intellectual exercise without relevance to my daily life, because I wasn't a parent. The dots didn't connect because they didn't have to. They weren't my dots.

And then my wife and I decided that we wanted to become parents. Adoption was something we'd considered, dithered upon, and mulled over for some time until we realized that if we were going to do it, we had to do it now, while we were still young (or less old). The thought of living a life filled with grief and regret that we hadn't become parents was too terrible to entertain.

During the process, we saw birth mother medical histories, with last names and addresses carefully redacted to preserve a hint of anonymity. All of them pregnant young women, all of them unable to become mothers, and all of them unwilling to undergo abortions. All of them very, very brave.

Months later, at the hospital, I watched my wife cradle the newborn baby who would become our son and years later ask us in a state two time zones away, "Did you grow me in yours tummy, Mommy?" She was the first person to hold him in love. She was his mother. The dots began to connect. They became personal. I became pro-life at that point.

Still, it wasn't enough. I had to intellectualize it. It had to make sense outside of the personal experience of being a dad. You can't advocate a policy just because it makes you feel a certain way: you need to defend it rationally. Bolster it. After all, there are millions of pro-lifers who aren't parents. Outside of the tenets of a particular religious faith, how do you get there?

It was faith that did it for me. As we know, one definition of faith is belief in something you can't prove. If you can prove it, it's not faith any longer: it's fact. It's not a faith-based proposition that water is wet, for example. We know it.

What we don't know is exactly when a human embryo becomes a person, with the inalienable rights that a person naturally possesses. We don't know for certain if there's a human soul, and if that soul suffers as a result of death. There's no way to tell the exact moment in time that a cell mass becomes a human baby. Because we can't know these things objectively, beyond any shadow of doubt, it becomes an absolute moral wrong to end that life for any but the most important of reasons. Convenience doesn't make the list.

This may be a sterile way of looking at the issue, but it's how I came to it. Any determination that at six weeks, six days, six months, or six minutes the embryo becomes or doesn't become a human being is, by its very nature, arbitrary. It's an attempt to know the unknowable, and unacceptably risk a life in the process. You can't know. You can't.

And if you don't know, if you can't know, then you mustn't kill it. It really is that simple. It's not about control of women's bodies (as though that were truly possible). It's about innocent life. It's about maintaining our humanity in the face of alternatives.

The coincidence of my little boy asking us the question that started this piece the night before the anniversary of Roe v. Wade is striking, but to the observant, the universe is filled with kismet. Had his birth mother realized her state of pregnancy earlier and been of a different outlook, he might have never been born. That's unacceptable. You see him, and you see a soul. You see a person. A medical professional or social scientist isn't qualified to determine when his personhood began.

So the dots are there: my wife, my son, and me. I connected them. He's connecting them, too.