You’re confused: as a definition, that can’t be circular. What makes it seem circular is that you also apply the common definition of “children,” which means “young people.” The above definition neither assumes that young people are less than fully rational, nor assumes that only young people can be irrational. By the definition, a six-year-old might turn out not to be a “child” at all, and an 80-year-old man might in fact be a “child.”
Who’s “they”? The definition means that, if you find an irrational human, you call him a “child.” And if you call someone a “child,” you’re saying he’s irrational. It might in fact be the case that no human fits that definition, in which case we conclude that there’s no such thing as a “child” in the sense of this definition.
If you reread carefully, you’ll notice that I included an existence proof. Namely, newborns aren’t fully rational, therefore newborns are children. That wouldn’t have needed pointing out, unless I recognized the possiblity that there’s no such thing as a child in the sense of this definition. I recognized it, and proved that there is such a thing.
If you reread even more carefully, you’ll notice that I specifically said a two-year-old might not be a child in this sense, which is precisely your claim.
Nope, you lose. An 80-year-old with dementia is also a “child.” As is a retarded 40-year-old, a brain-damaged 20-year-old, a mentally ill 35-year-old, and anyone else who isn’t fully rational. “Not fully developed yet” is one possible reason for being a child, but it’s hardly synonymous.
It suffices to prove that uttering the words, “I consent to a night of passion with Juan” doesn’t suffice to prove consent. The words can come out of a tape recorder, a parrot, a child in fear for his life, a child who has been coached, a drunken retarded insane person, etc. The ability to utter the words doesn’t suffice to prove consent. If you stop and actually consider the argument, you’ll admit it’s airtight. Something more is required.
–Len.