The word which would best encapsulate the tone and content of Steven Jensen’s latest book is “inviting.” It strikes a balance between density and readability. It does precisely what its title proclaims in providing a beginner’s (undergraduate level) introduction to Thomastic natural law. Jensen contrasts Aquinas with moral relativism, naïve realism, consequentialism, error theory and variants of natural law theory. Then he proceeds to divide his book into three parts.

In part one, Jensen outlines core principles, explaining how natural law is rooted in the fabric of the human person; it emerges from the divine construction of individual persons. The golden rule, for example, is a natural law. It is “[a]ccording to our nature [that] we should do unto others as we would have them do unto us” (115) (citing Summa Theologica I-II, 99,1 ad 3).

In part two, Jensen contends with the problem of harm. Under this heading, capital punishment, war, and self-defense are considered. He explains that to “do no harm” is an insufficient shorthand for all ethical dilemmas. In some instances, we must do harm in order to do the right thing. In his chapter on punishment, he asserts that “the harm (of being put in prison) is actually a kind of benefit” (154) insofar as it is medicinal for the prisoner; restorative.

Part three expands the focus to human societies. The family unit, governmental authority, and political life are considered. Controversial contemporary topics including monogamy and cloning are treated with sensitivity and clarity. The goal of political communities, Jensen explains, is not to advance human freedom and autonomy, but to aid in the formation of virtue:

The goal for which political society is instituted is the virtue of its members. The virtue itself, however, finds its meaning in yet a further goal; it is fulfilled only in virtuous friendship. The ultimate purpose of political society, then, is friendship.

(253-54) (citing Summa Theologica I-II, 99, 2). This simple assertion deserves further contemplation, since it is rather alien to the modern mind. But Aquinas felt that the reason for civil law, governments, and political exchanges was not to open up the potential for freedom of action. Governments are not justified on the basis of preserving self-evident freedoms. Nor are political societies founded on social contract. Rather, political communities are founded upon a shared good. Laws exist to provide an environment in which friendships can flourish.

To call the book “accessible” wouldn’t be too much of a stretch. It is far from dumbed-down. It is sensible, engaging, straightforward. But it demands careful attention from the reader. Undertaking a shared reading with discussion such as in the context of a book club might be preferable to reading the book solo. I recommend reading it with a friend.