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Ten Philosophical Mistakes

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Review of Adler, _Ten Philosophical Mistakes_

The thesis of this book is that Western philosophy has been for the most part in serious error for the last three centuries. Many people would consider that a sufficient reason to render the well-known judgment, "I couldn't pick it up." I note, though, that E. F. Schumacher makes a very similar claim at the very beginning of _Small is Beautiful_, and that book is so popular that our local university library has three copies. And there are other such cases in which courage is rewarded.

In any event, Adler's general argument is this: the important modern philosophers, beginning with Descartes, made certain errors which have had disastrous results for contemporary notions of the objects of consciousness, the nature of the human mind, the nature of language, of knowledge, of moral principles, of free will, and even the nature of happiness. Succeeding philosophers, especially Kant, instead of ferreting out these initial errors, tried instead to circumvent their consequences, thus in a sense compounding the errors. The errors were made due to ignorance on the part of modern philosophers of ancient and medieval philosophy, especially Aristotle and Aquinas. This ignorance in turn was due to the stultifying way in which the earlier doctrines were taught in late scholasticism, and also, no doubt, due to an over-zealous rejection of the past in the light of the new advances in material science.

Nearly all of the errors to which Adler points consist of failing to make certain distinctions. Locke failed to distinguish between those "ideas" which are truly private and do not point to things beyond themselves - sensations, feelings, emotions - and the "true ideas" which point to public things beyond themselves - percepts, memories, images. (This distinction was made by the scholastics.) Hobbes, Hume and Berkeley failed to distinguish between intellect and sense. (This distinction was made by Aristotle and Aquinas but carried to excess by Plato, Descartes, Kant and Hegel.) Locke also made the error just mentioned, and also failed to distinguish between pure or formal signs and other signs. Kant failed to distinguish between common experience and specialized experience. Everybody since the medieval period failed to make Aristotle's distinction between practical truth and descriptive truth. Dewey failed to make the distinction between terminal goals and normative goals. And so on.

Obviously it is important in each case to show that the distinction in question is not ad hoc - trumped up merely to resolve a single issue. For if we are allowed to create any distinctions we like, then nearly any position can be "refuted." Adler for the most part does note that the distinctions to which he appeals were made prior to the present difficulties, usually in ancient and/or medieval philosophy. But he does not do this in every case, and for me that is a weakness of the book. However, a single book cannot do everything; and a huge apparatus of footnotes would probably frighten away the very readers Adler hoped to reach.

In addition to the method of drawing distinctions that I have mentioned, Adler also often notes that the results of a given position are counter to common sense. He even makes the very strong statement "There is little if any sound philosophy that conflicts with our common-sense knowledge, for both are based on the common human experience out of which they emerge." p 106. This is problematic but by no means a weakness. In my field (linguistics) we very often had recourse to the expression "counter-intuitive." It would be rash to conclude that since many findings of science defy common sense, we can simply do without this notion. There definitely is something there. Why else should nearly everyone reject multiple universes, the most straightforward interpretation of QM, and one which preserves the normal meaning of probability? Why are the "brain-in-a-vat" idea, or the "Satan put the geological data there to deceive us" argument, never taken seriously for more than a few minutes, even though they are well within the realm of the logically possible?

Since I recommend the book highly - it is must reading for anyone who wants to understand what the leading philosophical issues are and have been; and it is the only book I know of that really does lay out the issues for the non-specialist - I will close by mentioning a few more negative points: Adler treats the emotions as completely subjective; yet it seems to me arguable that some emotions - e.g., fear - have public objects. On p. 15 he abruptly switches from the term "thought" to the term "concept." On p. 20 he introduces the expression "modes of apprehension" which we are not sure is synonymous with the earlier "instruments of cognition." Three notions are abruptly introduced into the book with no explanation; these are "the will" (part of intellect?), "theoretical construct" and "theoretical philosophy." Finally, in this book and elsewhere in his writings Adler regards philosophical theology as part of metaphysics; but in his recent work, _Adler's Philosophical Dictionary_ (1995), metaphysics is identified with philosophical theology.

After this book I would recommend Adler's _Aristotle for Everybody_ (1978) and then perhaps Peter Kreeft's _A Summa of the Summa_ (Ignatius Press, 1990).

Ken Miner

Mortimer Adler, as he would no doubt cheerfully admit, is not going to go down as one of the 20th century's great philosophers. But then, neither is the reviewer who calls him "all wet". For that matter, neither will any of us. It seems to me, therefore, that the tub-water response to his book is uncalled for, and possibly rather excessively arrogant, unless you happen to be a better philosopher than Adler; so I think it is only right to give a somewhat fairer review of the book, which I'll attempt.

"Ten Philosophical Mistakes" is something of a mixed bag. On the one hand, it contains a variety of quaint errors and outright misunderstandings. An example is Adler's apparent failure to understand that contemporary epistemologists use "belief" in such a way that it's simply analytic that whatever is known is believed. (Thus, he makes a big song and dance about a verbal point, warning us of the grave dangers of confusing belief and knowledge.) Again, there is considerable effrontery in the facile little argument whereby Adler hopes to defeat nominalism about properties. One might think, upon reading it, that men like William of Ockham and Jean Buridan (not to mention, in our day, Quine or David Lewis) just couldn't have been very bright to be taken in by such a stupid doctrine; yet strangely, they are accounted great philosophers. On the other hand, the book contains a number of useful pointers to major philosophical errors, which infected the entire modern tradition up to the positivist era, and continue to exert a baleful influence in many quarters of contemporary analytic philosophy. Two excellent examples, which Adler selects for special mention, are what we now call "sense-data theories", and the notion that it is impossible to refer to nonexistent (fictitious, imaginary) things. Adler is certainly right to point up the errors here. The first error has the farcical consequence that one can never see tables and chairs. The second has the even worse consequence that "Sherlock Holmes" is either not a name at all, or else Sherlock Holmes must exist. (The first alternative assaults the English language; the second is as silly as believing in the Tooth Fairy.) Adler's strategy, in each case, is to display the philosophical assumptions that lead to some absurd claim, point out that the absurd claim is absurd, and suggest that we abandon the assumptions in question.

It is idle to object that Adler hasn't refuted the arguments of those philosophers who advocated these errors, for as Adler clearly states at the beginning of the book, "I have not tried to argue for or prove the truths that I have offered as corrections of the errors pointed out. I rely upon the reader's common sense to discern that the corrections have the ring of truth." If Adler had promised refutations and failed to come up with them, that would have been worth objecting to, but he clearly says that he isn't attempting a refutation. Why, after all, should we have to refute something that we *know* is false? You might as well spend your time looking for the precise location of the hole in a sunken ship. Philosophers have argued, among other things: that time is unreal; that nothing ever moves from one place to another; that matter does not exist; that matter exists but tables and chairs don't; that not a single historical event could possibly have been the slightest bit different; that 2 + 2 might have been 5; that some contradictions are true. One metaphysician, Peter Unger, has even argued that he does not exist, and neither do any other human beings. As Cicero realized even in his day, there is nothing so absurd but that some philosopher has said it. Is it necessary to study and refute all the arguments that these philosophers have brought forth to believe the facts that they deny? I think not. Perhaps Adler's "common sense" is a bit overdone. But common sense overdone is a thousand times better than philosophy without common sense.

One of the most celebrated neo-classical philosophers of this decade is Mortimer J. Adler. Adler was born in 1902 in New York City and led a fulfilling life enlightening others even after his recent death in 2001. Adler began his career as a scholar with an education at Columbia University continuing there to teach psychology and then taught at the philosophy of law at Chicago University. He was the Director of the institute for Philosophical Research and most also the Chairman of the Board of Editors for the Encyclopedia Britannica.
The prologue to Adler's "Ten Philosophical Mistakes" begins with the following quote by Aristotle and best summarizes his thesis, "The least initial deviation from the truth is multiplied later a thousandfold." The implications of the this chosen quote is proved correct in this book; Adler dissects the blunders of post-16th century philosophers, namely those philosophers who followed Descartes and himself, and shows how the consequences have impacted contemporary society with confusion. Adler separates the errors of modern philosophy into ten of the following chapters: Consciousness and its objects, the intellect and the senses, words and meanings, knowledge and opinion, moral values, happiness and contentment, freedom and choice, human nature, human society and lastly- human existence.
The classical philosophers from the ivory towers had ideas that were so enlightening and their thoughts so deep that it could pierce the darkest questions of the universe; until the modern philosophers came along and totally demolished those towers that had taken centuries to build. It is true that society found that modern philosophy appealing because it was completely logical and coherent, more down to earth and applicable to their lives, but somehow it didn't seem to provide the enlightening affect that philosophy once possessed. That is until Mortimer J. Adler came along to rebuild the ivory towers; in this sense the book is successful because it steers you back towards the light. Even if one did not agree with him, you have to give Adler credit for his courage of challenging the darkest philosophers, and even more credit for widening your intellectual horizon with his "common-sensible" yet thorough ideas.
A prerequisite to prepare for reading this book is definitely to study the modern philosophers: Lock, Hume, Rousseau, Hobbes and Marx. These are the targeted axe-murderers of wisdom that have tarnished contemporary society's way of thinking according to Adler. Besides, once the theories of the modern philosophers are examined, one is always begging for an answer out of the deeper whole of black matter that they inflicted, Adler patches it up.
One of the reasons why "Ten Philosophical Mistakes" is so popular is because it is accessible to any literate person with a curiosity for philosophy. "Adler has the knack of steering readers through deep intellectual waters and making it easy to stay afloat," as the Pittsburgh Press puts it. Adler's use of language is exempt of much of the complex philosophical jargon that causes splitting migraines of confusion to the average person. That being said, there is another aspect that may cause many readers too loose interest in his arguments. In order to allow the general public to understand his book Adler is forced to spend excessive amounts of effort in defining numerous terms. Then again, when you look at it from another perspective, there would be no way to avoid this since most of the philosophical errors he lays out were caused by misinterpretations in the first place.
An example of Adler's extensive classifications of terms can be found in the very first chapter: Consciousness and Its Objects. To the average North American who spends more or less 10 hours a week watching television, understanding Consciousness would be an overwhelming task. But have no fear, Adler takes his time outlining as simplistic, thorough and exact as possible what consciousness and the concepts surrounding it mean from his perspective. As he does in most chapters, he then asks a set of profound questions regarding the concept at hand. In this chapter Locke's Essay Concerning Human Understanding is challenged. Once Adler has provided the reader with a stable understanding of the concepts and makes us aware of the errors of the modern philosopher, he is then capable of providing the solution. Chapter one concludes as follows, "The correction of that mistake produces the opposite result- a coherent view of consciousness and its objects that involves no inexplicable beliefs and that accords with common sense and common experience" (29).

I would above all recommend this book to three types of people. I suggest this to cynical people because modern philosophers did such a good number of plunging consciousness into a deeper and darker spiral, to people who couldn't get a grasp of philosophy because this book is based on common sense and is relatively easier than most philosophical books to read and especially to people who think they know all about philosophy because Adler will demonstrate otherwise.

The previous reviewer, I'm afraid, is all wet. Adler's book points out where thinkers of the past couple of centuries have arrived at conclusions which are simply wrong (i.e. nobody really thinks that way) because of flawed premises. Instead of re-examining the premises, as Adler does, said philosophers have made absurd claims about reality.

Adler's central premise is that the ancients were equipped with minds as good as ours, and therefore their philosophical conclusions deserve respect (their science is, of course, subject to correction).

Adler, by the way, is a neo-Thomist.

The following is my take on Adler's Ten Philosophical Mistakes. Please forgive my mistakes in advance and feel free to correct me here or via email at jldarrouzet@gmail.com.

1. Consciousness and Its Objects:
Mis-taking "that by which" we are conscious of our ideas, perceptions, memories, imaginations, conceptions or other objects of thought, for "that which" we apprehend during consciousness.

At the extremes, the former objects allow us to communicate at the highest levels of human experience; mistaking the latter for the former leads to solipsism, the assertion that everthing of which I am aware or conscious is a figment of my own mind.

All of us can partcipate in the former approach. It is commonsensical. There is only one solipsist, right?

2.The Intellect and the Senses:
Mis-taking the brain's ability to experience sensations for the mind's ability to intellectualize during cognition.

At the extremes, the former limits are mental functions to our brain's activities or lack thereof, and denies the existence of anyting that is non-sensible; the latter leads to artificial intelligence (the re-invention of angels). The former leads to a radical forms of materialism (nominalism, subjectivism, solipsism, complete skepticism, and cynicism); the latter to radical forms of idealism (archetypal universalism, conceptualism). We are human beings. Our brains are necessary for cognition and intellectualization, but they are not sufficient in and of themselves to act in those ways.

3. Words and Meaning:
Mis-taking the use of verbal description for significant communication of ideas.

"...our ideas do not have meaning, they do not acquire meaning, they do change, gain or 'lose' meaning. Each of our ideas is a mean and that is all it is. Mind is the realm in which menaings exist and whrough which everything else that has meaning acquires meaning, changes meaning, or loses meaning." "A meaningful word, a notation with significance, is a sign. Signs that are only and always signals are used by animals. Humans use signs that are signals and also signs that are form designators to refer to other mental concepts. Communication reduced to verbal descriptions using strings of code words amount to signals on an animal level. Communication of only strings of ideas amounts to an attempt at artificial intelligence. Commonsense communication works between the extremes. Naming is not merely asserting the existence of something or someone and giving it or him or her a description, but rather naming is an acknowledgment of a being that exists beyond the domain of my mind.

4. Knowledge and Opinion:
Mis-taking two different approaches for knowledge and restricting others to mere opinion: the approach of skepticism and logically positive sciences or the approach of phenomenalism and transcendental philosophy for knowledge.

At the extremes, skepticism masquerades as knowledge because it claims only empirical evidence to be real, but must resort to doubting doubt itself to provide a "private" proof of a possible starting point.

Likewise, logically positive sciences masquerade as knowledge by asserting axiomatically starting points from which to launch hypothetical proofs.

Rather than reach knowledge from this approach, we reach self-rightgeous indulgence of self.

On the other extreme, the raw data of phenomena is offerred as what is really known and all other views are pushed into mere opinion, thus rendering the intellectual enterprise an ultimately futile exercise of attempting to communicate beyond phenomenal worlds which may or may not be shared.

Likewise, transcendental concepts of the mind are invented and offerred to secure what is really known and all other views are pushed into mere opinion, thus again rendering the intellectual enterprise an ultimately futile exercise of attempting to communicate beyond transcendental concepts of the worlds which may or may not be shared. Rather than reach knowledge from this approach, we reach self-rightgeousness domination of others.

Based in large part on the mistakes noted in 1,2, and 3, these approaches fail to deliver what commonsense readily acknowledges. Few things are certain. Logic, mathematics, and definitions provide certain starting points for communication.

Most things have sufficient evidence to support our knowlege of them; but they move from opinion to knowledge based on accumulated viewpoints and observations and no relevant or pertinent contradictions. Science and commonsense experiences themselves exemplify this kind of knowledge. And finally, the knowledge that is not so supported is referred to as opinion.

5.Moral Values:
Mis-taking "right" moral values supported by opinions, built with might, for moral values with "might" supported by right, built with knowledge of what is good for human beings.

At the extremes, prescriptive judgments about what is "right" that comes
ultimately from power lead to subjective self-righteousness or moral relativism and resulting forms of hedonism or utilitarianism. Commonsense helps us understand that we address our natural needs before our acquired desires as a practical matter. At the same time commonsense teaches us to realize that the love of something or someone regularly commands our wills to take a course of action that satisfies our deeped hidden desires, and thus more than what we assess as needed.

6.Happiness and Contentment:
Mis-taking the psychological state of contentment for the ethical or spiritual state of happiness found in the quality of a morally good life.

At the extremes, both utilitarianism and the discharge of one's dutiful obligations masquerade as happiness.

Commonsense shows us that doing either what is useful or what is one's duty does not always assure happiness, though we may rest contented having acheived them.

7.Freedom of choice:
Mis-taking immature determinism or what chance means for indeterminism for what is meant by freedom of choice.

At the extremes, determinism allows rational choice, fails to recognize non-rational behavior, and thus leaves out the powers of our human wills, perhaps confusing them with our emotions. Indeterminism allows emotional choices by ultimately denying rational behavior, fails to recognize irrational behavior, and thus leaves out the powers of our human wills, perhaps confusing them with our reasons.

Commonsense tells us that freedom of choice is one of the defining characteristics of human beings and that because of it, we have the choice to reject determinism and indeterminism and accept judgment making and decision-making as practical alternatives to the certainty and uncertainty that determinism and indeterminism promote.

8.Human Nature:
Mis-taking humankind's animal-like physical behaviors or spirit-like mental behaviors for its human nature.

At the extremes, we human beings are mistaken for a different breed with determined bodily limits or we are mistaken for a different manifestation of one or many spirits.

Commonsense tells us we are neither animals nor angels, and surely not God (though, as creatures, we are God's children). We are a separate kind of being named human, with bodily limits, but with unlimited spiritual potential after our creation. Our minds, hearts, souls, and spirits are incarnated in our bodies, from conception most would say today. When we die, we are excarnated. We disappear. Those of us who belief in the after-life understand either a continuing set of many re-incarnations or a single recall into a new creation at the word of God. When that recall is assented to, God's word is so effective we are said to resurrect.

9. Human Society:
Mis-taking conventional theory of social contract for the origin of government as a human institution that meets the needs and wants of the naturally gregarious nature of human beings in society.

At the extremes, those on the "left" seek to treat individuals equally in all possible respects despite the differences among us by all conventional means. Those on the "right" seek to protect individuals unequal in some respects from the brutal people among us by all conventional means.

Because such approaches require conventional agreements, when they cannot be reached, people become frustrated to the point of overthrowing their governments. Yet, regardless of the government in power, commonsense tells us that human society continues throughout the duration of the conflict, not by centrist compromise but because of our naturally desire to live in society rather than as hermits.

10. Human Existence:
Mis-taking physical appearances or behaviors, or consciousness in human beings, for the only reality we identify with in existing things or persons.

At the extremes, on the one hand there are those who claim that material things are all that is real and that there is no non-material reality. Humans are no more and no less than material bodies having a limited capacity to transform energy over time. When they reach their limits, the human being dies and their body disintegrates. That's all.

On the other hand, there are those who claim that spiritual things are all that is real and that there is only non-material reality we call consciousness. Humans are no more and no less than spirits connected to illusory bodies with a unlimited capacity to transform energy over time. When they die their body disintegrates, but not their spirit. It returns and reincarnates until it no longer needs to. That's all.

Commonsense tells us human beings have bodies not the other way around. Commonsense tell us that our appearances and our behaviors do not tell everything about us or about any other observable thing. There's much more to the mystery of each individual. Commonsense tells us as well that we are conscious not only of ourselves but the reality of other subjects and other objects as well.

One can't help enjoy reading Adler. He writes with the layperson in mind, as if philosophy mattered to the laity, and it does!

Adler is not a "professional" philosopher, but that doesn't make his contribution any less worthy. Indeed, because of its accessibility and wide terrain, this is an engaging dialectic for most of the prominent philosophers from Plato to Nietzsche, One ought to keep in mind, however, that Adler at his death was a Thomist, and was an Aristotlean when he wrote this short volume. Expect, therefore, the criticisms of the philosophers chosen, e.g., Descartes, Locke, Hume, et alia, are skewered because they don't toe the Aristotlean party line. Despite his bias, Adler is fair in his criticisms.

Lamentably for Adler and his students, modern philosophy has made significant leaps since this book was written. Take the positive assertion that Locke's tabula rasa is right. Well, modern evolutionary biology, psychology, and congnitive science have disproved the tabula rasa theory. So, Aristotle, Aquinas, and Locke's "blank slate" notion no longer is true; defending it against the wealth of scientific experience opposing it isn't even a feature of this book.

So, who's this book for? Any beginning student of philosophy can benefit from Adler's reformation of some arcane, philosophical arguments in the language of the layman -- e.g., ordinary language. If one wants to know the fundamental flaws of the Empricists, for example, Adler adumbrates them. But before taking Adler's criticisms too seriously, be sure to compare them to current scientific thinking.

Adler, true to form, has bitten off in this work more than even he could possibly chew, much less any of us lesser mortals - to identify and conquer the noetical errors at the heart of modernism. Predictably, he has accomplished the first task far better than the latter: e.g., pinpointing nominalism as the root cause of modern evil is easier than sacking it, especially when you try to do so in less than three sentences. (And, yes, he really does seem to think he has logically disproven it in that many sentences.) Even novices like myself are bound to feel the errors in question worthy of a little more thoroughness than Adler grants them. But perhaps the process of sleuthing should be seen as Adler's primary task here (as he himself claims), and if that is the case, then he has accomplished it with ease and grace. He does not rest with the symptoms of modern relativism (either moral or dogmatic), but goes to the very heart of the matter, dissecting the way we humans think and judge in a masterful way, and better yet, demonstrating that we way these things are done simply do not mesh with relativism. More to the point, Adler's arguments will be convincing only to the already converted; it strains the imagination to picture his keen reasoning bringing a hardened modernist to his knees. His success, I think, lies in helping his fellow classicists (like myself) to purge the last remnants of Enlightenment rationalism from the deepest corners of our minds.

The frustrating thing for me, as someone who considers himself already somewhat narrow-minded, is how Adler's can manage to be even narrower. I stumbled once, twice, thrice over trains of thought where I couldn't quite follower Adler to the end: he denies flatly that universals have any existence in reality (p. 73), categorizes mathematics as a discipline whose object is not reality but conceptual notions (p. 103), and mocks Plato for thinking happiness could be found in virtue alone, without wealth (p. 143). It's not that I necessarily disagree with Adler here (though I think I do), but that I think intelligent people can disagree on these questions and still stand apart from the 'erroneous moderns' against whom Adler rages. It is in his final chapter that the author 'shows his cards,' simultaneously revealing to me why I disagreed with him more often than I had anticipated. Finally admitting his confessional stance, Adler apologetically insists that "it is possible to be an Aristotelian without being doctrinnaire about it" (p. 96), but methinks Adler is a bit more doctrinnaire than he thinks. Still, apart from a few sticking points, Adler has done a fine job in plunging yet another dagger into the heart of a dying school of thought (if it is not already dead, at least at its font), and his book will be of enormous value to almost any reader.

We have all heard people say, as if it were a message from the divine, words to the effect that philosophy is either dumb or not needed and one can't make any sense from it. Mortimer Adler made it his life's work attempting to demonstrate the importance of philosophy in leading a civilized life.

Adler has been criticized for his conservatism, his allegedly Euro-centric viewpoint, and his refusal to adapt many of the nouveau philosophical ideas currently floating in and out of favor. Adler demonstrated one truth: COMMON SENSE IS NOT ALL THAT COMMON.

Drawing strength from Aristotles laws of logic, he traces the development of philosophical mistakes that over the course of time have been compounded into mass errors. He shows that many times it is easier to take the simpler way out, philsophically, rather than fight for the ultimate truth. Adler views humankind differently than many philosophers, seeing us as differnt in kind (rather than just degree) from the animals. And like his mentor, Aristotle, he teaches that what distinguishes us from other animals is our ability to reason and think analytically.

Not only has he been involved in philosophy in general but he has also been active in applying such a viewpoint to the real world. His educational proposals have wrought incredible results when implemented. His proposals on teaching ideas have resulted in thousands of young philosophers armed with a new knowledge for facing the world.

Starting in the Medieval times, he identifies several errors in philosophical thought that have changed not just how we think but how we think about ourself as individuals and as a species. Mortimer Adler is a national treasure!

I would highly recommend this book to everyone as a nice answer to the cultural relativism of today - or "postmodernism" if you would prefer. Essentially he gives a very good case that we really do exist and that yes, you are responsible for your actions. Also, happiness isn't the main goal in life, and by the way - there is an absolute right and wrong (and it isn't based on the existence of God).
Adler could be dogmatic about his views but I think he had a very good reason - his reasoning and logic would stand up under scrutiny.
I didn't give it five stars because at points he was a bit redundant and I think the writing style wasn't always as lucid as it could have been. But, those are very minor criticisms.

As Adler himself admits, the title of this book is inaccurate, since it covers more than ten philosophical mistakes. I'd like to add that it also makes more than ten philosophical mistakes. This is not to say that the book is without value. Adler is a very clear writer, with a kind of conversational style that makes complex issues seem easy. But for the most part he also treats these issues too simplistically and ignores problems with his own views. The issues are not that easy, after all.

To consider just one example, take his defense of moral objectivity. His basic argument is that subjectivists ignore that there is a basic prescriptive (or normative) truth which, along with descriptive truths, can be used as a foundation for objectively true moral judgements. This basic prescriptive truth, according to Adler, is that "we ought to desire whatever is really good for us and nothing else" (p. 125). And, he adds, the reason we know this is so is that it is a self-evident truth, meaning that it is impossible for us to think otherwise. But that's obviously not the case. It is very easy to imagine thinking that we ought to desire what is not good for us. Suppose, for instance, that someone has no interest in living much longer, no interest in being in good health, etc. Then they may believe that they ought to do things that are bad for them, e.g., for the sake of enjoyment.

And even if that were not the case, there are other problems with Adler's use of this one "truth" as a basis for moral philosophy. For instance, how do we settle disputes between two parties when each desires what is really good for themselves but where their desires conflict?

Adler does make some good points, especially on the first chapter ("Consciousness and Its Objects"). But any potential reader should be aware that there are good counter-arguments on almost all of these issues.