Leo Strauss, History and Natural Right - Chapter 5

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Locke is a hedonist: "That which is properly good or bad, is nothing but barely pleasure or pain." But his is a peculiar hedonism: "The greatest happiness consists" not in enjoying the greatest pleasures but "in the having those things which produce the greatest pleasures." It is not altogether an accident that the chapter in which these statements occur, and which happens to be the most extensive chapter of the whole Essay, is entitled "Power." For if, as Hobbes says, "the power of a man...is his present means, to obtain some future apparent good," Locke says in effect that the greatest happiness consists in the greatest power. Since there are no knowable natures, there is no nature of man with reference to which we could distinguish between pleasures which are according to nature and pleasures which are against nature, or between pleasures which are by nature higher and pleasures which are by nature lower: pleasure and pain are "for different men...very different things." Therefore, "the philosophers of old did in vain inquire, whether summum bonum consisted in riches, or bodily delights, or virtue, or contemplation?" In the absence of a summum bonum, man would lack completely a star and compass for his life if there were no summum malum. "Desire is always moved by evil, to fly it." The strongest desire is the desire for self-preservation. The evil from which the strongest desire recoils is death. Death must then be the greatest evil: Not the natural sweetness of living but the terrors of death make us cling to life. What nature firmly establishes is that from which desire moves away, the point of departure of desire; the goal toward which desire moves is secondary. The primary fact is want. But this want, this lack, is no longer understood as pointing to something complete, perfect, whole. The necessities of life are no longer understood as necessary for the complete or good life, but as mere inescapabilities.The satisfaction of wants is therefore no longer limited by the demands of the good life but become aimless. The goal of desire is defined by nature only negatively - the denial of pain. It is not pleasure more or less dimly anticipated which elicits human efforts: "the chief, if not only, spur to human industry and action is uneasiness." So powerful is the natural primacy of pain that the active denial of pain is itself painful. The pain which removes pain is labor. It is this pain, and hence a defect, which gives man originally the most important of all rights: sufferings and defects, rather than merits or virtues, originate rights.[...]The painful relief of pain culminates not so much in the greatest pleasures as "in the having those things which produce the greatest pleasures." Life is the joyless quest for joy.
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Emphases in bold are my own. While I have reservations about Strauss, I think that his account of Locke and the modern natural law tradition poses a serious challenge to any Catholic who wishes to defend both classical liberalism and traditional Catholic political doctrine, which is typically grounded in the Thomistic natural law concept.