One of the most familiar refrains of the past week or so, i.e., during the run-up to the anniversary of Roe v. Wade and Monday's March for Life, was that we as Catholics, know that abortion is wrong.
I submit that this formulation is in all cases harmful to the cause of life, and in most cases indicative of a faulty understanding of how the Church teaches what She teaches.
It is most emphatically not as Catholics that we know abortion is wrong.
If real assent to the truth of revelation were necessary in order to recognize the intrinsic evil of procured abortion, then the pro-aborts would be right.
The data of revelation provide us with more information about human dignity (about its contents, about its source and about its end).
That, however, is entirely beside the point: human reason dictates that abortion is wrong. Not only: reason also shows that positive legal sanctioning of the practice is contrary to the essential ends of political power.
Said differently: there are some things that we know are true because the Church teaches them.
Examples are: that God is one Being in Three Persons; that He created the universe and all that is ex nihilo; that He took on human nature in order to redeem it and to save the whole world.
There are other things that the Church teaches because they are true.
Examples are: that the universe has an intelligible structure; that human reason is capable of penetrating that structure and arriving at true and certain knowledge of the source of all that is; that the moral order is an integral part of the stucture of the universe; that the direct, deliberate destruction of innocent human life violates the moral order that is built into the universe.
If it were otherwise, i.e., if it were rather the case that human reason is incapable of knowing that the direct and deliberate destruction of innocent human life violates the moral order that is built into the universe, then one of a series of alternatives would necessarily obtain: either the universe would be lacking in an intelligible structure, or human reason would be - on principle - incapable of understanding the structure of the universe.
If the former, i.e., if there were no intelligible structure to the universe, then there would literally be no universe (no cosmos, as the Greeks so neautifully called it). If the latter, then every society of human beings would be nothing more than an external power structure, in which the strong lord it forever over the weak.
As things stand, however, there is an intelligible structure to the universe, and we know it: when human beings first turned their gaze to the heavens, they found something wondrous in their ability to measure the stars in their courses. They found community between Earth and Heaven, where they expected only vacuous infiinity between God and man.
This discovery had consequences: people who made it could no longer pretend that their attempts at ordering their lives together on Earth were a matter of indifference to the universe, or to the author of the order they had begun to discover.
So, they began to study the heavens, to search for the ultimate reason behind the movements of the heavenly bodies - and this, with a view to ordering their own lives together in concert with the heavenly order.
The attempt to measure the movement of the heavens is physics, and the attempt to penetrate the source of order behind the movement is metaphysics - but the attempt to order our lives together is politics, and the attempt to understand how best to do so according to measure and reason is political science (episteme politike).
In other words, our political (social) life - remember that Cicero translated Aristotle's zoon politicon as animal socialis - is governed ultimately not by force, but by reason, and this is a fact of history, empirically verifiable: not a conjecture.
So, we are left with an alternative: either abortion is wrong, or nothing is.
But, if abortion is wrong, then it is wrong by the same reason that gives birth to stars: one can know this reason without knowing that the author of it was a Jewish carpenter born during the reign of Caesar Augustus in the Roman province of Palestine.
It is our ability to know the reason, which makes us capable of living together in society.