Many pro-choice arguments would be unthinkable if applied to a toddler. It's a good tactic to "trot out the toddler." Show the absurdity of the argument by showing what it would mean if applied to a toddler. It refocuses the argument on the one question that matters: What is the unborn?
A lot of people don’t realize that virtually every single argument offered in favor of abortion—given the rationale that they give—is just as adequate an argument for taking the life of a newborn child (infanticide). And because this is true, it is effective to point that out in a conversation. This is a version of the “Taking the Roof Off” tactic: you take the point-of-view of the person seriously and you give it a test drive and see where else it leads. So, if a woman has a ‘right to choose,’ then we can take that and apply it to the newborn child.
Does a woman have a ‘right to choose’ to take the life of her own newborn child? This is called, “Trotting out the Toddler,” where you put the toddler up for display and say, “let’s apply your rationale to this child.” This works because there is no relevant difference between the unborn and the born. Because the child is the same thing on either side of the birth canal, there is no magic when the baby travels down that seven-inch journey from inside the womb to outside the womb.
A lot of philosophers, nowadays, have understood that any rationale for abortion inside the womb becomes a rationale for infanticide outside the womb. This is why we use the tactic, “Trotting out the Toddler.” We take the rationale that is given to kill the child in the womb and we say, “What about this two-month-old child?” In almost every single case, the reasons why it’s justified to abort the child in the womb would apply to this child. They are both human beings at either stage of development. They are full and complete human beings. They are just in different locations. Now, since location is morally trivial—“Trotting out the Toddler” and applying the argument for abortion to infanticide—many times this is going to give a person pause. This is why we use, “Trotting out the Toddler.”