You speak of what we “can’t not know,” but surely children don't already know the natural law.

Correct.  When we speak of things we can't not know we have in mind people who have reached the age of reason.  That's why I've sometimes described the natural law as what we can't not know "or can't help learning."  Although I suspect that even children know more than you think.  When Billy steals Susan's cupcake, Susan knows enough to cry "Not fair!", and Billy knows enough to lie about it.

You mean so that he won't be spanked.


But doesn't that show he doesn't know he did wrong?

No.  It shows that violating one known duty gives Billy an immediate motive to violate another.

So you think even pretty young children know some of the natural law.

Yes.  Some of it.

But not all of it.

Not all.

But if children don't know all of it, then it isn't innate knowledge after all.

Who said it was?

Don't all natural law thinkers say it is?

No.  That's a common misconception.  When you say "innate," you mean something like "born with us."  How could the newborn baby know that gratuitously hurting people is wrong, when he doesn't even know that there are people?

But if the so-called first principles aren't innate, then how can you call them "first"?

They aren't first in the order of time, but in the order of reason.  They are the unprovables from which proofs are built.  The reason it takes a long time to know things like "Gratuitously hurting people is wrong" is that it takes a long time to form concepts of gratuitousness, hurting, people, and wrong.  Our minds are so made, however, that as soon as we do grasp these concepts, we immediately recognize that gratuitously hurting people is wrong.  The technical expressions are that although the precept is not innate, it's per se nota, "known in itself," "underived."

I don't buy that.  If everyone knows certain precepts, it's only because everyone is taught them.

In that case it's mighty strange that everyone is taught the same precepts.  How do you explain the fact that the same ones are taught everywhere?

The same ones aren't taught everywhere.  Christians restrict a man to one wife; Muslims permit up to four.

We were talking about basics, not details.  Show me a society that doesn't recognize the institution of marriage!

But that's only for the preservation of the species.

I thought you were trying to tell me that there isn't any natural law.  Now you're trying to tell me why there is.

No, what I mean is that I concede the reality of instincts.  All this talk of "conscience" is just mystification.

Morality is not an instinct.  If it were, we might think we should resist it, but we wouldn't be able to.  The facts are just the opposite.  We can and do resist it, but think we shouldn't.

So maybe it's not an instinct; call it a predisposition, or just prudence.  It's still about preservation.  We want our kind to survive.  Sometimes what is needed for survival goes against my personal wishes, that's all.

Who do you mean by "our kind"?  What helps a family to survive might not help the larger society to survive.  What helps society to survive might not help a particular family to survive.

I mean our species.  I'm talking about the human race.

That's a little arbitrary, isn't it?  Don't people want their families and their societies to survive too?  Besides, morality isn't about whether the human race survives, but about what kind of survival it gets.  We marry; guppies don't.  We don't eat our young; they do.  Yet neither species is in danger of extinction.

A Dialogue on Natural Law, Part 5