The most important book published in political philosophy in years is Arthur M. Melzer’s Philosophy Between the Lines: The Lost History of Esoteric Writing. It first of all establishes, beyond all reasonable doubt, that philosophers (and poets, and other writers) routinely deployed “a double doctrine.” One was “exoteric” or “external” and “public.” The other was “esoteric” or “internal” and “secret.”

The intention of the French philosophes—or enlightening, publicizing philosophers— was that the truth about these two contradictory doctrines become public knowledge. They turned esotericism into an exoteric or public doctrine. And Melzer, a professor of political science at Michigan State University, explains why the Enlightenment thinkers did this. It was part of their attempt to bring about a world in which esoteric writing would no longer be necessary, where philosophers would no longer be persecuted for telling inconvenient truths.

In their ideal society, there would be no conflict between justice and human excellence. The residual esotericism that they themselves used was, in their minds, a temporary tool to purge the world of superstition and prejudice. This “political esotericism” of the authors of the Encyclopédie was in the service of an open society with perfect freedom of thought.

We could also describe their ideal world as a place without irony and double meanings, where esotericism would be remembered as that device which good men, such as Plato and Aristotle, had used to protect themselves from political and religious oppression.

The Encyclopédie authors outed esotericism as one way of making it a past-tense phenomenon. Soon, the kinds of things Plato and Aristotle said secretly could now be said plainly: for example, that religion is nothing but a political tool. Or that the risky virtues are for suckers. Or that there’s no other reason to obey the law than enlightened self-interest. We could add: Love is an illusion. Philosophy is basically the most intense and enduring form of hedonism. Suffering is meaningless. And death is personal extinction.

The ancient philosophers thought that society couldn’t handle anywhere near that much truth; social stability depended upon a veil of ignorance when it came to God, love, death, virtue, and civic attachment. The Enlightenment, the political project of modern philosophers, proved the ancients wrong. All those shocking truths are now the common sense of literary sophisticates, from Woody Allen to the author of the children’s book and movie The Fault Is in Our Stars. And the popular adoption of these truths does seem compatible enough with the stable family lives of our “cognitive elite” today.

Our “new atheism” is nothing but an off-the-shelf version of the old or esoteric atheism. Enlightenment’s result has been that religious and political cruelty continue to fade; we continue to purge ourselves of the residual illusions that hamper achievement of the reasonable goal of keeping the people around right now secure and free for as long as possible.

Melzer proves that the intellectual history of esotericism wasn’t the perverse invention of Leo Strauss and his arrogantly deceptive Straussians. Any scholar who doesn’t acknowledge the fact of esoteric writing is literally cut off from the deep wisdom of the past. But Strauss is a very significant figure in this history. He, even more than the 18th century Enlightenment authors, made a big deal of the esoteric/exoteric distinction. He wrote to restore it as a fairly public doctrine, a doctrine that would orient public intellectuals and even beginning undergraduates. He, too, wanted the awareness of esotericism to be a mood or attitude that wouldn’t just be for potential philosophers anymore.

Strauss, Melzer shows, was somewhat—but not mainly—drawn to esotericism as a political tool. It’s true that Strauss did encourage his students to ally with American conservatism and defend American law and morality against various forms of corrosive, even if somewhat truthful, dogmatic skepticism and progressivism. So some Straussians insist that Americans must believe in the absolute truth of the principles of the Declaration of Independence, even if the privately Epicurean Mr. Jefferson was somewhat ironic about them.

But other, wilder Straussians, such as Laurence Lampert, say that it’s good that the Enlightenment and modern science continue to march toward a global triumph, and that the time for esotericism is over. Lampert criticizes Strauss for not having been loud and proud about his atheism and about “the sovereignty of becoming.”

Judicious Catholic Straussians, such as Pierre Manent, consider whether the Enlightenment has led the West to revel self-destructively in post-political, post-religious, and post-familial fantasies, and whether it is now time to ask if there aren’t limitations to the philosophers’ secret account of who each of us is, given that those private philosophical musings have become (in a distorted way) our public doctrine. Our Supreme Court, after all, has explained that the American idea of liberty evolves over time, which might mean that it purges itself of “political esotericism” and becomes all about personal autonomy or unfeigned Epicureanism.

We can say that many of our Straussians are ham-fisted enough in their esoteric efforts that a reader begins to wonder if they really mean what they say. With the best of them, their expressed devotion to God, country, and family is not feigned because they realize there is more to real life than being a philosopher. That would mean, of course, that the best of the Straussians don’t really think that Socrates taught the whole truth and nothing but.

My own view is that Straussian writing doesn’t work all that well when its main purpose is to defend “healthy” political life that is the precondition for the future of philosophy in the world. One reason is that our view of personal identity—which includes our inalienable natural rights—depends upon a Christian insight that discredits an in fact fairly exoteric Socratic teaching about the supposedly radical difference between the liberated life of the philosopher and the slavish life of everybody else—those benighted denizens of “the cave” or the city.

Consider that Socrates distinguished himself from the philosopher-kings by locating himself in the cave; and that his philosopher-kings are an exoteric, poetic construction two steps removed from reality (just as the character Socrates of the Republic is one step removed). Thinking of almost all people as “citizens” or successfully socialized to be part of the whole called the city and its regime was, for Socrates, an educational technique developed in response to Glaucon’s tyrannical idealism. It was not Socrates’ complete description of who particular persons are. Christianity introduced into the world a more vocal criticism of both the natural theology and the civil theology of the Greeks and Romans. Particular persons with singular destinies and irreducibly “inward” beings can’t be reduced to a part of nature or a part of a country.

Modern philosophy, as Melzer shows, accepted or at least deployed the Christians’ skepticism of politics. Religion and political life remain separated, and personal identity is understood to be free from political or natural determination. And so America’s self-understanding has never been as a “regime” or a whole that corresponds to the non-philosophic soul. Melzer says that modern liberal or Enlightenment philosophy’s intensification or elaboration of the key Christian insight actually obscures the truth that the key human distinction is between philosophy and poetry. More precisely, he says that this distinction was the foundation of multidimensional classical esotericism, although it hasn’t been been the foundation of either Christian or modern, liberal, philosophic Enlightenment.

“All men are created equal” can’t be vindicated these days by anyone who views it as an exoteric teaching or merely the foundation of a public philosophy. The classical political thinkers, following the noble lie in the Republic, thought that the founding myth that all citizens are created equal had to be defended to keep political leaders from treating their fellow citizens as resources to be exploited. For them, equality was promulgated as a civic or public—not a natural or inward—truth. The classical political philosophers also thought, as Melzer explains, that slavery was indispensable for high civilization and therefore for the flourishing of philosophers. They were fine with that offense against what we regard as “social justice,” and they were more than a bit ironic about the often tyrannical longings that fuel the human longing for perfect justice.

Aristotle, it’s true, is an exception, for he can be proved to have shown—although with great reserve, or even esoterically—that the convention of slavery does violence to what we really know about human nature. But that means that he was fine with the indefinite perpetuation of a despotic institution he knew was unjust. He accepted that slavery in some sense would always be with us.

The unironic defense of human equality depends, I think, on viewing every human being as a unique and irreplaceable person, a being with an irreducible personal identity. That questionable thought—it might be regarded as dogmatic—depends on bringing to the table more than the secret truths of the pre-Christian philosophers. It’s that questionable thought, we might say, that made esotericism merely political or provisional. In a Christian or an enlightened world the need for it would wither away. Slavery, as even St. Augustine suggested, would disappear, as would the vain pretensions that were the foundation of the patriarchal exclusiveness of political life.

Just as the City of God doesn’t distinguish between Jew and Gentile, Greek and barbarian, man and woman, or philosopher and citizen, there would be a reconfiguring of political life—the exoteric or public world—under the influence of the deep truth about who each of us is. In this way, political life could be become a contract among free persons to preserve the peace and facilitate the inward relational life that is the flourishing City of God. And true theology would be the cause of the disappearance of civil theology. The American Constitution dispenses with God as the foundation of political life, but it does so to protect the free exercise of religion.

In the case of Mr. Jefferson, his public devotion to all human creatures equally possessing inalienable natural rights and his corresponding eloquence against the cruel violence of slavery were compromised by his private Epicureanism, his heartfelt praise of the philosophic life that flourishes beyond hope and fear. In his public actions, Jefferson was altogether too serene about slavery’s indefinite future. It is possible—even necessary—to be somewhat ironic about “natural rights.” The rights-obsessed person, in Jefferson’s philosophic view, is caught between Epicurean serenity and the dutiful life of the parent, friend, citizen, and creature. But is it possible to be ironic about the real existence of the significant human person and be devoted to the American “public philosophy”?

But to get back to Strauss: His invaluable contribution, as Melzer meticulously explains, was to restore esotericism as a perennially relevant teaching method—and not just for potential philosophers. (We so often forget how rare Strauss thought philosophers were. It’s at least a question whether he regarded Diderot or Voltaire as philosophers—and certainly not Thomas Paine nor Mr. Jefferson nor various of today’s leading Straussians.) From an educational view, as Melzer shows, the main problem with liberal society today is inauthenticity, a problem that intensifies as we work to reconfigure all rights around personal autonomy or “human rights.” Jean-Jacques Rousseau complained that no one in the society around him was really a citizen or religious believer or a parent deep down; all bourgeois lives are consumed by “role playing.”

That goes especially for our allegedly liberated intellectuals. They pronounce all kinds of terrible truths, but they don’t really seem to be moved by them. They aren’t driven by wonder or awe or even real anxiety. They don’t really understand that philosophy, or science, should be learning how to die. They’re already dead to, or diverted from, themselves. They care mostly about how they look in the eyes of others. Our scientists, it’s true, sometimes more authentically lose themselves in the cosmos or their impersonal theories, but that still means that they are, when it comes to an inward consideration of their own natures, diverted.

Strauss wondered, and Melzer with him, why the truth about esoteric writing’s past pervasiveness disappeared from our scholarly world. Maybe the best explanation is that the denial of the reality of esotericism is, at its most self-conscious level, a form of esotericism that serves the relativism that privileges what passes for wisdom nowadays.

The relativistic or “historicist” thought is that what is thought and said can be explained by the worldview or values or authoritative prejudices of a particular time and place. That means, for example, that Plato and Aristotle were basically apologists for the Athenian way of life, its conventions. A thinker can transcend only to a small degree his place in history. That mode of interpretation of the philosophers of the past depends on collapsing any distinction between their exoteric and their true doctrine, and then finding the result wanting from the point of view of the wisdom we believe we possess now. In a society where esotericism has become superfluous, it’s better to not remember that it was ever deployed in the past.

Not only can one now write distinctly and clearly, without doing harm to oneself or anyone else, it’s even possible to forget that anyone ever wrote differently! The denial of esotericism locks each of us securely onto the surface and in the present, allegedly for our own good (and certainly with our own self-esteem in mind).

In Melzer’s view, the denial of esotericism is a way of numbing people to the terrible truths they would rather avoid. It used to be that philosophers kept people from really feeling the hard truth by supporting comforting illusions that cover it over. This enabled people to live authentically as citizens, creatures, parents, friends, and such. They acted on what they believed about God, love, family, and country. Because they were passionately attached to serious opinions about the fundamental issues, a teacher of philosophy could work with what they thought they knew, to lead them in the direction of the truth about those issues. The way to being a philosopher, the mature Socrates thought, was through questioning the assumptions that animate “earnest provincialism.”

Melzer is open to the possibility that the numbness of inauthenticity promotes social stability as well as the salutary illusions used to do. But it turns out that it’s worse for genuinely higher education—philosophic education—to encounter a society in which genuinely dangerous thoughts seem almost impossible. No writer in America today really fears the fate of Socrates.

But he can have, as Walker Percy said, a kind of Solzhenitsyn envy (which might be understood as a version of Socrates envy). Solzhenitsyn’s subversive defense of the truth against ideological lies caused him to be taken so seriously by his now-defunct country, the USSR, that he was thrown into the Gulag and eventually just kicked out. (And today we American authors might envy the dissidents still truthfully writing between the lines in places like Iran, China, North Korea, Cuba, and elsewhere. For them, truthful words about freedom make a big difference, or even all the difference.) A novelist or professor in today’s America can say just about anything and people pretty much yawn. It’s true that Straussians and Christians who teach in our mainstream colleges have to be prudently reserved until they get tenure. But big deal.

Melzer’s only real objection to stability through authenticity is that it poses unprecedented obstacles to philosophic liberation. In my view, he follows Allan Bloom in exaggerating the flatness of soul of sophisticated middle- and upper-middle-class Americans. It’s just not true that they have become so affectless that they are no longer moved by love and death. Solzhenitsyn, in fact, was probably closer to the truth when he observed that just beneath the surface of America’s pervasive happy-talk techo-pragmatism, he heard the “howl of existentialism.”

Ask a sophisticated American what idea, today, would constitute a dangerous idea. Frequently the response is an idea that unnecessarily exposes a person to risk factors by promoting irresponsible or unhealthy personal behavior. Insofar as we become reflexively skeptical of the soul, and the corresponding virtues and intellectual disciplines, we become obsessed with personal survival. People are more aware than ever of their personal contingency and haunted by the prospect of personal extinction. They are ever-aware of death, even as they refuse to accept its inevitability. There may be no more inauthentic life than one fueled by one-dimensional survivalism, with an aversion to danger that’s both more natural and more dogmatic than the conventionalism that animated the political opponents of Socrates. It’s this survivalism that causes us to put our faith in the technology that can save us, as well as the completely safe separation of sex or eros from birth and death.

The problem with a world where all communication is supposed to be clear and distinct, where there are no real secrets or elusive mysteries about the human soul, is that we lack the words—more precisely, we lack the modes of attentive reading and listening—that correspond to our real experiences. Although there are many motivations for and ways of writing esoterically, it is, on one level, introducing what poets and novelists characteristically do into the prose of specifically philosophical writing. It’s better to show the truth than to tell it straight out.

The teaching method of Allan Bloom was, I think, a kind of exoteric exaggeration of the extent to which the individualism of Enlightenment rationalism has emptied relational life of its content. And so, Bloom explained, the true choices in our time are philosophy or nothing: living authentically with the truth about one’s own mortality, or living inauthentically with it. The exaggeration that “capitalism” or “the Enlightenment” had transformed everything about us, which Marx employed to call us to political revolution, Bloom employed to call us to the hard truth about being a particular person who was born to know and die. And Melzer, by describing inauthenticity as our leading social problem, reminds us of the common debt that Bloom (and Strauss) and Marx owed to the anti-bourgeois and proto-existentialist Rousseau. For many an existentialist, being authentic is being alone; but for the Straussians, there’s also the philosophic compensation for the misery of mortality that comes with the joy of figuring out and sharing with others the truthful insight about who we really are. And insofar as that sharing is through writing, it has to be esoteric, because truthfully authentic lives will always remain few and far between.

That teaching method, I can’t help but notice, has opened many young men and women to the possibility of philosophy, and it’s not true that America today is short on highly educated and thoughtful Straussians convinced of the superiority of the philosophic life to all others. The idea of esotericism has turned out, in their cases, to have roused them from their bourgeois slumber. But I would say that they couldn’t have been roused if their souls had really become flat, if they hadn’t yearned to be a lot more than nothing. It wouldn’t work if they didn’t, that is, have longings that pointed beyond their biological beings as either social or solitary animals.

I have done readers the disservice of barely touching on the actual content of this wonderful book, which allows us to share abundantly in the author’s joy of discovery. If I had a quibble, it would be that he doesn’t give us, at least straight out, an example of esoteric wisdom that would be shocking even to us in our atheistic time. It might be the case that the fact of esotericism dazzles a lot more than its actual content. Or it might be that we can’t expect Melzer to make a big deal out of being, as they say, genuinely transgressive. Those who buy the basic argument of his book, after all, now have every incentive to start reading it between the lines.