Last time I introduced the idea of foundationalism and ended on Descartes’ most basic truths found by a thought experiment of complete doubt of long held beliefs. To some extent the next three centuries of philosophy offered responses to his method and conclusions. None seemed to deny the truth of the Cogito, ergo sum, though Thomas Reid chided his colleagues that only a philosopher would feel it necessary to prove his own existence. However there was strong disagreement about this dualism of separate mind and body, skepticism about his ontological proof of God, and challenges to the reliability of the senses.

Nonetheless, the foundationalist quest continued. Roger Scruton offers the example of  J.G. Fichte who thought philosophy must discover the ‘absolute unconditioned first principle of human knowledge.’ By taking Descartes’ first truth that “I am” and adding the law of identity (A=A), he derived I = I, a supposed bedrock truth. “All knowledge begins with self-knowledge, and the self is the center of the world.” This self is transcendental or subjective, not the object of knowledge, while everything else is non-self. The implications of self as subject transferring all no-self to object is fundamental to later German philosophy, but it too is repudiated, in this case by Schopenhauer who called it sham philosophy.3

If Descartes’ and successor attempts failed, there was still one paradigm of foundationalism- mathematics. That is until the late 19th century, when holes began to appear in its presumptive certainty.4 It started with non-Euclidean geometry that undermined space and shape; for example the angles of a triangle projected onto a sphere do not add up to 180 degrees. Then George Cantor displaced the reliability of numbers from their pedestal with his studies on infinity showing “there are an infinite set of infinite numbers and these obey different rules than finite numbers” – so if you add the infinite set of rational numbers between 0 and 1 and the infinite set of irrational numbers between 0 and 1, you end up with a larger infinity!

Kurt Gödel followed with his proof that we can never establish a complete set of rules for arithmetic and that any system of logic will invariably lead to unresolvable paradoxes equivalent to sentences such as  “This sentence is false” where, if false, it must be true; but if true, it must be false. Strengthening the rules to eliminate these paradoxes then leads to true sentences that cannot be proved.

For the moment, it seems philosophy has failed to provide a bedrock foundation for truth and knowledge. If mathematics and pure thought experiments like that of Descartes are refutable, then there seems little expectation we will ever find absolute certainty. This of course leaves us with knowledge of limited certainty, but perhaps meeting Adler’s criterion, ‘beyond a reasonable doubt’ – enter now skepticism which challenges whether we can know anything at all, and is the subject of my next blog.


1Belief, that happens to be correct, in the absence of evidence, is not knowledge but mere opinion.

2Several of the pre-Socratic Greek philosophers attempted to identify the fundamental nature of the cosmos. Thales postulated the “basic stuff” was water, Anaximander called it the ‘limitless,’ and Anaximenes thought it was air (these three are known as the Milesians). Pythagoras thought underlying reality was number, and Heraclitus fire. Each would justify his belief and derive the visible universe from his originating element.

3Scruton, Roger, An Intelligent Person’s Guide to Philosophy. Penguin Books. New York, 1999. ISBN 0 14 027516 9, page 44-45.

4Gimbel, Steven, Mathematics in Crisis, in Redefining Reality: The Intellectual Implications of Modern Science, Steven Gimbel, The Teaching Company, 2015, Lecture 3.



“I have arrived at the rock bottom of my convictions. And one might almost say that these foundation-walls are  carried by the whole house.” – Ludwig Wittgenstein, On Certainty.


Now that we have thought through some of the intricacies of certainty and truth in their objective and subjective dimensions, we are ready to take on the two extreme philosophical positions in this area: foundationalism – the quest for unquestionable basic truths that can be parleyed via logic into a rigorous system of truth; and skepticism – the belief that nothing, (or extremely little) can be known with certainty. Today we will address the former.

Knowledge is often defined by philosophers as belief justified by evidence.1 However each piece of evidence must itself be justified by other evidence creating a chain which backs up to an axiom, or unsupported  truth. Such axioms are supposedly unquestionable or self-evident; and thus constitute the putative foundation of knowledge.

Foundationalism is descriptive word rather than a movement, and hence there is no accepted history. John Dewey seems to feel that early human societies felt so vulnerable to forces in nature they did not understand that they defaulted to deity, superstition, and prayer. In that environment, God emerged as both absolute reality and the source of divine knowledge inaccessible to humanity. Scripture, the purported ‘word of God’ revealed certain truths. Meanwhile more secular societies such as the Greeks and the Chinese sought foundations of knowledge in simplistic understandings of nature2, but also pure logic, and mathematics. This search for ultimate reality resulted in a misleading distinction between theory and practice and a dichotomy between the spiritual/intellectual and the material/practical realms. In brief, the premature quest for a foundation of knowledge actually slowed humanity’s advancement.

Rene Descartes appears to be the first modern thinker to depart from this tradition when he decides to doubt every belief he has ever had and identify the most fundamental truths possible. His path leads him to the following four indubitable truths: (1) “I think, therefore I am,” (2) mind is distinct from body (one can imagine oneself without a body, but not without a mind), (3) God exists (the idea of God and perfection must originate from God, not from an imperfect and finite being), and (4) God, as a perfect being, would not create us with senses that deceive us about the existence of the world. These principles are usually seen as the first specific instance of foundationalism.

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“An objective uncertainty held fast in an appropriation-process of the most passionate inwardness is the truth, the highest truth attainable for an existing individual” – Soren Kierkegaard, Concluding Unscientific Postscript





In our investigation of certainty, we have arrived at the exploration of the subjective manifestations of truth. In the last two blogs we looked at four of them: pragmatic instances, individual perceptions, the observer’s role in knowledge, and internal reality. Today we delve into Kierkegaard’s existential subjectivity.

In his masterpiece, Concluding Unscientific Postscript, Kierkegaard challenges the 19th century view of truth as objective reflection, arguing that this process makes the subject (the knower) indifferent or accidental, and hence the most objective knowledge possible entails the vanishing of the subject, the knower herself. But Kierkegaard sees this as illogical; knowledge and truth must be possessed by an existent being, who alone can have interest in truth. The objectivity which comes from denial of the subject can be at most “an hypothesis or an approximation.”1 “All essential knowledge relates to existence, or only such knowledge as has an essential relationship to existence is essential knowledge.” 2

Compared to objectivity, “subjective reflection turns its attention inwardly, and desires in this intensification an inwardness to realize the truth…an identity of thought and being.”3 Reality consists only of existing individual things, thus existence and truth are indelibly individual in character. Thought is fine as long as it is existentially rooted because the subjective thinker is at the same time a thinker and an existing human being. Since existence is a continual process of becoming, logic and pure thought can never quite capture it. 4

Kierkegaard stumbles onto one of the most sublime thoughts in all of philosophy: “Truth is subjectivity.” By this I believe he is referring to personal truth, not scientific facts. This inner truth is the only truth that matters to the individual as individual, that which is “true for me… a truth I live not merely observe… which I am , not merely posses. Truth is a mode of action or a manner of existence. The subjective thinker lives the truth; he exists it.”5 Examples of such truths concern love, life decisions, the future, death, immortality, and God. They always involve uncertainty; that is, subjectivity and uncertainty are coextensive. When objective knowledge and certainty is placed in abeyance, inward passion intensifies toward the infinite and at least in the case of God, faith is the result. Compare this with the objectivity of a mathematical proposition with its indifferent certainty. 6

Kierkegaard’s thought process is admittedly difficult to follow and abbreviate. However I think most of us understand the difference in the significance of certain truth like the formula for the area of a circle, whatever its practical use, versus the truth of our limited lifespans, the love of our spouse, the nature of our inner self, or our concept of ultimate reality. Subjective truth, it seems to me, trumps objective certainty when considering the meaning of life and the pursuit of happiness.


1Cahn, Steven M. (editor), Classics of Western Philosophy. Hackett Publishing Company, Inc., Indianapolis, IN, 1999. ISBN0-87220-436-7, page 882.

2Ibid., page 884.

3Ibid., page 883.

4Magill, Frank, Masterpieces of World Philosophy in Summary Form. Harper&Row Publishers, 1961, page 628.

5Ibid., page 627

6Cahn, Steven M. (editor), Classics of Western Philosophy. Hackett Publishing Company, Inc., Indianapolis, IN, 1999. ISBN0-87220-436-7, page 887.


Last time we saw how the pragmatism of William James incorporates subjectivity within truth, and how empiricism’s reliance on perception imposes a quality of the subjective on much knowledge. Today we investigate two additional subjective features of truth. We start with John Dewey, a pragmatist and follower of James, who attributes a vital role of the knower in knowledge. Dewey argues that knowledge is ‘eventual,’ that is the outcome of directed experimental operations rather than something existing before the act of knowing. He is particularly struck by the significance of the observer with respect to Heisenberg’s principle of indeterminacy. “Knowing is seen to be a participant in what is finally known. Moreover, the metaphysics of existence as something fixed and therefore capable of literally exact mathematical description and prediction is undermined.”5

Our fourth subjective feature of certainty and truth concerns the first of the five tiers of reality identified in an earlier blog, internal reality or that of the individual’s mind.6 Here I must challenge Professor Adler on his thesis that all knowledge must be public, never private, and that nothing knowable by only one person can have the status of knowledge.7 Perhaps this is fair with respect to evidence in science, where accessibility to others is integral to the scientific method. But with respect to our personal knowledge, it seems arbitrary to assume inner truth is logically impossible simply because it cannot be directly observed by others. The individual alone can identify his innermost primal self, existential truths such as his continuity with his past self that instantiates his identity, and transcendental truth such as the unity of self and cosmos. Rene Descartes argues rather convincingly that our own consciousness is the most certain thing we are aware of while Martin Heidegger finds the direct knowledge of our own being is the platform for understanding all being.

In conclusion we see that much of what we consider truth and reality is not purely objective, but at least partially subjective, but we are not through. Next time we will look at the most passionate arguments ever given for truth as subjectivity in the writing of Soren Kierkegaard.


1  James, William, Pragmatism and The Meaning of Truth. Harvard University Press, Cambridge, Massachusetts, 1978. ISBN 0-674-69737-5, pages vii-xxx. The introduction is written by A.J Ayer.

2 James, William, The Varieties of Religious Experience. Penguin Books, New York, NY, 1985. ISBN 978-0-14-039034-6, pages 423-424.

3James, William, The Will to Believe. Dover Publications, Inc., New York, NY, 1956. Pages 1-31.

4James, William, Pragmatism and The Meaning of Truth. Harvard University Press, Cambridge, Massachusetts, 1978. ISBN 0-674-69737-5, page 121.

5Dewey, John, The Quest for Certainty. Minton, Balch, and Co. New York, NY, 1929. Page 204.

6See Internal Reality on this site – November 12 and 14, 2018.

7Adler, Mortimer J., Ten Philosophical Mistakes. Macmillan Publishing Company, New York, NY, 1985. ISBN 0-02-064120-6, page 89.


“In our cognitive as well as our active life  we are creative. We add, both to the subject and predicate part of reality. The world stands really malleable, waiting to receive its final touches at our hands…Man engenders truth upon it.” – William James, Pragmatism.

Now we come to a major obstacle in assessing certainty, do we actually understand the nature of truth and knowledge?  Can we box all truth up in a package of objectivity, of absolute pre-existing reality with our knowing as simply incidental? The answer is surprising, even unsettling, and is the focus of the next three posts. On reflection there are at least five facets of truth that are not objective, but subjective (in approximate order of increasing depth):

1.    Pragmatic truth

2.   Sensation

3.   Observer impact on reality

4.   Inner reality

5.   Relational truths

First let’s take up pragmatism, where truth is seen as the utility or instrumental function of an idea. Its best known advocate is William James who divides philosophical temperaments as tender-minded (truth as rationalistic, idealist, religious, or principle-based) or tough-minded (truth as empiricist, materialistic, irreligious, fact-based). Clearly the tender-minded outlook is more subjective while the tough-minded is more objective. Materialists like Bertrand Russell and A.J Ayer are brutal to James, a physician turned philosopher, who see his pragmatism as implication that truth is relative.1

But James offers a simple example that seems to me to be inconvertible evidence of at least some subjective truth. Assume you come across a chasm and must decide whether you can jump across it. Here the subject alone determines the truth, for if you believe you cannot, you will not and the truth of your belief is confirmed. If you believe you can, and then jump it, your subjective truth is verified when you do (we will not consider the decision to jump and fail).2 Of course James believe the subjective truth of pragmatism is more extensive, applying to other circumstances.

James considers another example: the subjective truth of mystical experience. It seems arbitrary for one to say to another that his mystical experience is not real  because it can neither be shared nor proven.3 But this opens up the door to contesting empiricism itself. If our experience of reality is the measure of truth, then the subjective sensations of each individual define truth at least for that person. As we discussed in an earlier blog, it seems irrational to deny a person has pain when he sincerely claims to be in pain. Likewise if a color-blind person says red and green traffic lights appear identical, we might say his sensation is inconsistent with our own and offer scientific arguments against him, but we cannot say that his experience of them is untrue. Human sensation is always subjective; we only assume (and hope) our sensory functions are consistent as a species.

Human concepts also involve subjectivity: the Big Dipper is a recognizable constellation to most men in the northern hemisphere, but not presumably to the cosmos. Is it real? True? Certain? A final example is the six-pointed star; is it two triangles or a hexagon with legs on each side? Are both descriptions true? Or is neither true? Dependent on the observer?4

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We ended last time on Kant’s two categories of knowledge, the a priori and the a posteriori.  The concept of a posteriori knowledge requires further refining, especially distinguishing ‘authentic’ knowledge from mere opinion. Science and investigative history count as the former even though they are corrigible and mutable, whereas individual beliefs and personal taste do not. Since reality usually refers to the ‘knowable’ independent of the ‘knower,’ it follows that knowledge must be public, not private, that is, nothing knowable by one person alone can have the status of knowledge.7 Moreover, authentic knowledge is the result of directed experimental operations and investigation processed through disciplined reason.

But what is the criterion of truth? In the course of human history, philosophers have identified three theories of truth:

1.    Correspondence – truth is what corresponds to reality or fact (the common idea of truth).

2.   Coherence – truth is that which coheres with other truths or beliefs (includes convergence).

3.   Pragmatism – truth is that which can be used to guide behavior; that is ‘what works.’

Since empirical knowledge is never certain and always amendable, the most prudent course is to use all three when possible, rather than choose one, in order to achieve the greatest confidence possible of any statement.8

Finally there is the question of how to circumscribe a corpus of truth and authentic knowledge in a world of assumptions, misconceptions, error, prejudice, and unjustified opinion. It begins with the recognition that the validity of a belief is not correlated to the passion of its adherents. The philosophical tool of doubt – the greatest legacy of the ancient skeptics – is the prelude to whatever truth and certainty is possible for men. From there investigation may uncover relevant evidence and reason may offer cogent arguments, that an open dialectic or debate filter into knowledge of the highest confidence. While still potentially flawed, such information meets an acceptable standard for guiding ethical behavior.

These last two posts contain an implicit assumption, that knowledge, truth, and certainty are purely objective. Next time we will blur the picture by considering subjective features of truth.


1Webster’s New Universal Unabridged Dictionary, Barnes & Noble, Inc. 2003. ISBN 0-7607-4975-2, page 339, definitions 1 and 4.

2Edwards, Paul (editor), The Encyclopedia of Philosophy. Macmillan Publishing Co., Inc. & The Free Press, 1972.   Volume 2, page 67.

3Webster’s New Universal Unabridged Dictionary, Barnes & Noble, Inc. 2003. ISBN 0-7607-4975-2, pages 2029 and 2031

4Ibid. Page 1064, definitions 1 and 7.

5Adler, Mortimer J., Adler’s Philosophical Dictionary. Simon and Schuster, New York, 1996. ISBN 0-684-80360-7, page 53.

6Adler, Mortimer J., Ten Philosophical Mistakes, Macmillan Publishing Company, 1985. ISBN 0-02-064120-6, page 83.

7Ibid. Pages 89-90.

8See my post Current Reading – Truth this site dated 11/16/2018.


“Doubt is not a pleasant condition, but certainty is absurd.” – Voltaire.

Understanding certainty depends on thinking through its subtle meanings, the definitions of knowledge and truth as distinguished from opinion and belief, and the philosophical tools of doubt and reason. Let’s start with the word “certain.” Webster’s had several definitions, but the two most useful here are: (1) free from doubt or reservation, confident, sure, and (2) established as true or sure, unquestionable, indisputable.1 By these definitions, we can say it is certain that 2+2=4, but not that God exists. Philosophically, certainty refers to the relational property of statements or propositions rather than a simple state of mind. Its opposite is “doubtful”, while the intermediate status is “probable.” All of these qualify our judgements rather than designate the truth value of the statement; for example, statements can be certainly true or certainly false.2

Webster’s defines truth as “conformity with fact or reality,” true as “being in accordance with the actual state,” and fact as “something known to exist or to have happened.”3 Knowledge is defined as (1) acquaintance with facts, truth, or principles as from study or investigation or (2) the body of truths or facts accumulated in the course of time.4 Therefore, what is certain is known or knowledge, but not vice versa. In addition anything known must be true; while of course opinion and belief may be true or false.

Mortimer Adler takes a juridical approach to knowledge; dividing it into three baskets of falling certainty – (1) beyond a shadow of a doubt, (2) beyond a reasonable doubt, and (3) by virtue of a preponderance of the evidence – where only the first may be considered “certain.”5 He also considers truth and certitude as immutable and incorrigible, whereas empirical knowledge and opinion are both mutable and corrigible.6

Socrates was the first to recognize that the philosophical quest for wisdom distills into the pursuit of virtue, and the most fundamental requirement for virtue is knowledge. Thereafter the history of philosophy became identifying reliable knowledge or certain truth. Over time two forms of knowledge were identified, perhaps most clearly explained by Kant: analytic or a prior statements and synthetic or a posteriori statements.  There are now more commonly referred to as self-evident and empirical statements.

A priori statements do not depend on any sensory experience and are thought to be true or certain because their opposites are self-contradictory. Examples include (1) “A part is less than the whole,” (2) statements of identity such as “2 = 2,” and (3) “All human experience occurs within space and time.” The breadth and value of such knowledge is limited as it is most often truth by definition even if not always immediately evident. This form of knowledge is manifested in logic and mathematics.

A posteriori or empirical statements are based on experience; for example “grass is green.” There is nothing contradictory about grass being any other color, it is only our consistent experience of its color that makes this statement true. Science, history, politics, law, and individual opinion are all manifestations of this form of knowledge.

It should be added that there remains debate on whether any knowledge is a priori ; some philosophers including David Hume argue that all man’s knowledge requires experience even for the reasoning that is assumed to be innate.

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“I tore myself away from the safe comfort of certainties through my love for truth; and truth rewarded me.” – Simone de Beauvoir

When I first decided to write a book titled Philosophical Guidance, the use of the practical or speculative philosophy of the great thinkers to pattern a meaningful life, I planned as preparatory work a description of reality and ethics followed by an exploration of some limited, mostly unambiguous special topics: good and evil, God, death and immortality, free will, teleology, and suffering. I specifically hoped to avoid the more formal and tangential disciplines of epistemology and logic. However earlier investigations came back again and again to the issue of certainty, and I have come to see that effective guidance is utterly dependent on having a means to distinguish knowledge which can be relied upon from that which is suspect. The fulcrum of all understanding and decision making comes down to the skill in appraisal of levels of certainty and doubt, and on one’s level of confidence in knowledge and action. Thus I propose now to take on this subject despite its theoretical difficulties.

As in the past I plan to break up this complex topic into its constituent parts:

1.   Introduction.

2.   Definitions and distinctions

3.   Truth and subjectivity

4.   Foundationalism

5.   Skepticism

6.   Coherentism

7.   Science and certainty 

8.   Perils of certainty

9.   Confidence levels (statistics)

10. Personal table of certainty

11. Synopsis

We will begin with a clarification of terms and subtleties of definition. Next will be the distinction of truth from certainty and a brief look at Kierkegaard’s epigram: “Truth is subjectivity.” From there we look at the opposite ends of the poles of certainty: (1) Foundationalism, the search for absolute certainty; and (2) Skepticism, the doctrine that nothing can be known; followed by a brief look at a reasonable middle ground – Coherentism. Then we assess science as potential certainty with particular attention to the opposing concepts of falsifiability and verifiability. Next we examine the dangers of certainty: the inevitability of error and the potential harm of strong but unfounded opinion. In closing we will revisit statistics to understand the concept of “confidence level,” and I will present my attempt at a chart of certainty or confidence, before a final synopsis.

Join me next time as we start with definitions and distinctions.


Next in The Good Old Liberal Consensus, Daniel A. Kaufman examines wisdom in the political realm as described in John Locke’s Second Treatise of Government and John Stuart Mill’s On Liberty. Briefly they inform the ‘liberal consensus’ which is based on the theory that the clashing of people’s interests and aims is inevitable, that the state is a neutral referee, and that an individual’s pursuit of good should be unmolested except when obstructive to another individual’s pursuit of good. From this foundation, four key principles arise: (1) the purpose of the state is to allow the individual to pursue his idea of the good, (2) thought and speech should be free, (3) the state should err on the side of free speech, and (4) engagement with those with whom one disagrees should take the form of discourse not personal attack. These principles are supposed to be sustained by the collective recognition that unanimous agreement on policy is implausible and that one’s political allies cannot be in power forever. However, in his opinion, this wisdom is being undermined by both the Right and the Left.

Last Valerie Tiberius entertains a more psychological sense of wisdom through the contemplation of a single adage, also her essay’s title: Live Each Day as If It Were Your Last. The power of this advice is its tendency to alleviate worry and excuse perfectionism. More generally it encourages the development of perspective that aligns emotions with what really matters. She places it within Aristotle’s practical wisdom or phronesis, the use of reason to apply knowledge to decision-making. But Tiberius suspects this proverb may not do justice to what really matters. She references Doing Valuable Time: The Present, The Future, and Meaningful Living by Cheshire Calhoun who divides one’s time into four parts: (1) “primary spending” – things done for their own sake (e.g. time with friends), (2) “entailed spending” – instrumental activities (e.g grocery shopping, studying), (3) “norm required” – compliance with societal norms (e.g. legal duties), and (4) “filler spending” – such as actions when waiting, unmotivated, or tired. Meaning comes mainly from primary spending while things we value require significant entailed spending.  Her conclusion is that one can take the ‘last day’ perspective sometimes, but not at all times – wisdom then is the ability to shift one’s perspective as circumstances require.

Interestingly the essays look at four distinct levels of wisdom – personal, psychological, societal, and political – quite a breadth for the limited size of this forum. Wisdom is revealed to be virtue first, but also preparedness, freedom, and perspective. Aristotle suggests a still higher category, ‘speculative wisdom’, the philosophical knowledge of metaphysics and theology, as opposed to the others he calls ‘prudence’. I love these many facets of wisdom, but distill from it the blending of a coherent understanding of reality with ethical conduct.

1Garvey, James (editor), The Philosopher’s Magazine. Issue 87, 4th Quarter 2019, pages 82-105.


“To know how to grow old is the master-work of wisdom, and one of the most difficult chapters in the great art of living.” – Henri Frederic Amiel, 19th century Swiss philosopher.




The Forum in the fourth quarter 2019 issue of The Philosopher’s Magazine is titled Finding Wisdom, and consists of four essays – a total of only 18 pages of reading. In the introduction, we learn this project arose in response to letters requesting more practical philosophy. The authors are two men and two women professors of philosophy who were asked to take up a single philosopher or school.

Massimo Pigliucci’s piece, Wisdom: What Is It? examines the Stoic tradition. Following Socrates’ thought that wisdom equates to virtue as it is the only intrinsic good that cannot be used to do evil, Seneca offers the corollary: “Virtue is nothing else but right reason.” Such reason can be defined as “fitting expertise” in the “art of living.” Pigliucci suggests three tools for mastery of this art: (1) reading biographies of persons to emulate (e.g. Cato), (2) review of theoretical treatises (such as Seneca’s On Anger), and (3) study of practical books (e.g. Epictetus’ Enchiridion). From these we learn the cardinal virtues of courage, justice, temperance, and practical wisdom which allow us to center our lives with a moral compass to achieve arête, the best way of living.

Catherine Wilson follows with Epicurean Wisdom wherein subjective pleasure and the avoidance of psychological and physical pain and deprivation are seen as the highest human goods when paired with the avoidance of selfishness and harm to others. This doctrine historically urges one to avoid unnecessary political and social involvement preferably by living in a communal setting with like-minded individuals. Wilson sees this as a problem for modernity as most of us do not wish to withdraw from society; instead she extrapolates the following lessons for contemporary living: (1) oppose oligarchy legislatively, (2)  seek not eternal youth and longevity nor fear death and inevitable deterioration, rather prepare for them, (3) support justice defined as the prevention of harm,  and (4)  deploy utilitarian governance as the societal expression of Epicureanism.

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