In this article, Hadley Arkes responds to J. Joel Alicea’s review of Arkes’s book Mere Natural Law.

Although Alicea acknowledges that judges should consider the natural law, he says he cannot justify judges using a substantial amount of their own morality when executing laws. Alicea claims that in Mere Natural Law, Arkes “conflates principles of reason with principles of morality.” Arkes responds that this is exactly what he does. The most basic mark of human nature is using reason to determine what is right and what is wrong.

Alicea then argues that most scholars agree that the Constitution was not originally understood to authorize federal judges to act on their own moral reasoning. Arkes counters that argument. Quoting John Marshall in the case of Fletcher v. Peck, Arkes explains how a law can be determined wrong outside the text of the Constitution if the law’s “wrongness was rooted in a principle that did not depend at all for its validity on being mentioned anywhere in the text of the Constitution.”

“My pitch, then,” Arkes says, “Is that, at times, the judges must reach out to the plainest truths that are engaged in the case, even though they are not contained in the text, and do it simply for the coherence of their judgments.”

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