Adler begins his latest book with Aristotle’s admonition: “The least initial deviation from the truth is multiplied later a thousandfold.” Adler concludes with a recommendation: “The recovery of basic truths, long hidden from view, would eradicate errors that have such disastrous consequences in modern times.” For 10 delightfully lucid chapters in between, he uncovers and corrects the “initial deviations” that have generated the contemporary short-circuit in philosophical thinking.

Consider Locke’s postulate that an “idea” is that which the individual apprehends,” instead of that by which the individual apprehends some object.” If we take Locke’s theory seriously, then the bottle of wine between us on the dinner table is not real, but “an idea in our minds.” Locke did not even need common sense to discover his error; he could have consulted Aquinas, who, good Dominican that he was, had demonstrated that the wine was real, and that ontological teetotalism such as Locke’s prohibited “the possibility of our having any knowledge of a reality outside . . . our own minds.” Still, many have taken Locke’s notion seriously and its tangled outgrowths—skepticism, subjectivism, and solipsism—prevail today.

Consider also the assertion of Hobbes, Berkeley, and Hume that the human mind is a mere “sense-perceptor.” As a purely sensitive faculty, Adler says, the mind would not have any abstract ideas. Man could not apprehend the objects of mathematics, nor conceive metaphysical objects such as God or the soul, nor converse about such abstractions as liberty, justice, virtue, and the infinite: “None of these can be perceived by the senses. None is a sensible particular.” But of course men can conceive of such things (even Locke conceded that “Brutes abstract not”); the intellect—the part of the mind that does not simply receive and react to sensation—is one great attribute that makes us different in kind, not just degree, from other animals. Nonetheless, the mistaken view of the human mind persists, undermining individual responsibility and making human life less inviolable and—the shame of the 20th century—more expendable.

In correcting other mistakes, Adler applies special scrutiny to Hume and Kant, whose works represent opposite faces of the same error: the definition of “knowledge” as exclusively the product of methodical investigation and probative data. By this definition, philosophy and metaphysics are discounted as mere “opinion,” and “real knowledge” becomes the possession of specialists who progressively insulate their microcosmic subjects from the corpus of knowledge and the experience of the human race. Philosophy and the collective experience of mankind, Adler argues, ultimately are more essential to human existence than the germ-free bubble of the “expert”; without them, we are unable to understand everything else we know, and the path to happiness and wisdom lies dark and untraveled.

In the latter half of the book, Adler addresses less esoteric mistakes, such as the “astounding, yet in our days widely prevalent, denial of human nature.” Adler wonders, too, how the human race survived long enough for Hobbes, Locke, and Rousseau to invent the “state of nature” and “social contract” theories if the family and rudimentary society are not “natural.”

Adler insists that the philosophical mistakes are simple ones and that their proliferation is the result of “culpable ignorance”:

They are ugly monuments to the failure of education—failures due, on the one hand, to corruption in the tradition of learning and, on the other hand, to an antagonistic attitude toward or even contempt for the past, for the achievements of those who have come before.

The solution is to reopen the philosophical classics of pre-17th-century Western civilization, which have answers that a shallow and dissipated contemporary philosophy cannot provide. Adler is convinced that these landmarks will help us to undo the mistakes that promote needless misery in modern times.



[Ten Philosophical Mistakes, by Mortimer J. Adler (New York: Macmillan) $12.95]