In issuing the “Manhattan Declaration,” Christian leaders across the nation declared their intent to stand for the dignity of the unborn and the institution of marriage even up to the point of civil disobedience. Unsurprisingly, this declaration has spurred much commentary, not all of it sympathetic. One could predict the standard objections from groups and persons committed to the culture of death, but more noteworthy are objections rising from a camp one might expect to agree with the document: namely, a certain kind of conservative Protestant, often, although not always, of a strongly Calvinistic tendency.

One might expect this group to value traditional marriage, oppose abortion and embryo-destructive research, and defend religious liberties strongly, and they do, and yet many in this group have reacted quite negatively to the document. The reaction intensified, at least in the blogosphere, after a New York Times Magazine piece on Robert P. George, one of the leading signers of the declaration.

Some of this is the usual antipathy towards Roman Catholicism, which remains severe enough to prompt even a signatory like Dr. Albert Mohler to feel the need to explain his association with the document. The main intellectual objection is precisely the one mentioned in the Times piece, namely, “that [George] puts too much faith in the power of reason, overlooking what Christians describe as original sin and what secular pessimists call history.” The notion that the natural law forgets sin and thus depreciates the necessity of Christ and the supremacy of Scripture is an old one, to be sure, and is a common objection raised against the ethics and theology of Thomas Aquinas by this same group of Protestants. For example, James White states that George’s position is “a direct refutation of the biblical view of the supremacy of divine revelation and the corruption of human reason through sin,” and Phil Johnson claims “the biblical truths of original sin and human depravity [pose] a fairly fundamental challenge to Robert George’s notion that society can be won to righteousness through human reason alone.” And these are among the more moderate objections. The influential Protestant apologist Francis Schaeffer spoke for many when he characterized Aquinas as believing “the will was fallen or corrupted but the intellect was not affected.”

Certainly Thomas held that the first principles of the natural law could not be erased from the human being (ST I-II 94.6), and neither did sin fundamentally negate human nature, for if human nature were to be essentially changed by sin then our first parents were of a different species before and after the first sin. A nature cannot change essentially without changing the essence of a being, after all.

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But only a wooden and uncharitable reading of Aquinas stops here, for Aquinas has a sophisticated view on the question. He holds that the prelapsarian human was endowed with the grace of original justice, a rectitude whereby reason is subject to God, the lower human powers subject to reason, and the body subject to the soul. Such a person would not sin because he or she is properly ordered; without concupiscence, the unfallen human would always follow the dictates of right reason. Original sin, among other consequences, deprives the human of this original justice, destroying the harmonious relation of human powers to each other and to God.

Since the will is for Aquinas a rational appetite, the will is directed to the good of the whole person rather than to some power or part of the person. While a particular appetite, say for food or sex, seeks only its particular satisfaction, the will integrates and directs all these competing desires into a whole, into a human act, which is why humans can, for the sake of their own and the common good, control their desires to consume too much food or fornicate with this or that person. Particular appetites are directed and placed in order by the rational appetite.

Given original sin, the rational appetite is inordinate and can act counter to right reason. We do disobey the divine mandate, we do allow lower appetites to dominate reason, and we do allow the goods of the body to triumph over the goods of the soul. Further, given original sin and the loss of human integrity and rectitude, we do suffer what Thomas calls the wound of ignorance, that is, we can voluntarily ignore truth and the desire for truth. We can, and do, act in cunning fashion, whereby reason is bent to devise new and clever evils in service to inordinate desire.

There is no cheery optimism in Aquinas with respect to reason. The human is disordered;, one might even say we suffer a totality of depravity since not a single human capacity or function remains in the state of original justice. Yes, humans are utterly messed up, but they are still human beings, and as human beings, as rational animals, they still possess the natural law, for to lose the natural law would be a loss of humanity, actually to become a beast. Not, that is, to act bestially—humans do so—but to be a beast. And this has not happened, since original sin does not change our essence—nor could it. The basic human goods remain the same basic human goods for Adam and for Hitler, and the flourishing of human persons qua persons has not changed. But sin does change our willingness to function as we ought, as we can all attest.

There is, then, no contradiction between the natural law and original sin, at least as understood by Thomas Aquinas. The “Manhattan Declaration,” therefore, remains the declaration of cosmopolis, for insofar as the declaration is reasonable it is reasonable for all, even us sinners.