Philosophy and the Problem of Achieving Certainty

Introduction

The philosophical quest for certainty, especially in matters of being and logic, is one of the oldest and most fundamental tasks shaping the development of Western thought. This problem has its roots in ancient skepticism, which questioned the possibility of attaining any reliable knowledge, and reaches its apex in modern European philosophy, where the pursuit of indubitability becomes the driving force for constructing entire systems of knowledge. Thinkers such as René Descartes sought to find unshakable foundations for cognition, attempting to overcome all-encompassing doubt and establish criteria of truth that could guarantee absolute certainty. However, as we will see, this path often led to new paradoxes and limitations, forcing subsequent philosophers to rethink the very nature of certainty.

At the same time, there are other traditions offering alternative approaches to the problem of certainty, not always aiming at its absolutization. For example, empiricism, represented by John Locke and David Hume, shifts the emphasis from rational deductions to sensory experience, asserting that our knowledge of the world derives from sensations and reflection [Locke, 1689]. This, in turn, raises questions about the reliability of such knowledge and how universal it can be. Immanuel Kant, attempting to reconcile rationalism and empiricism, proposed his critical philosophy, which sets the limits of human cognition, showing that some questions traditionally attributed to metaphysics lie beyond possible experience and, therefore, cannot be the subject of certain knowledge [Kant, 2000]. The problem of certainty in philosophy is not merely a search for answers but a continuous refinement of what we can know at all and how we can be certain of it.

Within these philosophical traditions arises a deeply personal question: can a person ever reach a state of peace regarding their greatest uncertainties and fears? In other words, is there a philosopher who has truly achieved certainty concerning being, logic, or anything else? This question touches not only epistemological aspects but also existential ones, since uncertainty often generates anxiety. We will examine how various philosophical schools have approached this problem, from Descartes, who sought indubitability in his own thinking, to contemporary approaches that may offer acceptance of uncertainty as part of human existence.

The goal of this lecture is not to provide a definitive answer to this question but rather to analyze different philosophical approaches to achieving certainty, identify their strengths and weaknesses, and show how philosophy itself can serve as a tool for reflection and possibly reconciliation with inevitable uncertainty. We will explore how philosophers have tried to build systems of knowledge on solid foundations and why these attempts often led to revising the very concept of certainty. Ultimately, we will see that the "world" in relation to uncertainty may lie not in its elimination but in a deep understanding of its nature and place in human experience.

Detailed Exposition

What is the Nature of Certainty in One's Own Existence: Phenomenological or Rational?

Can we be absolutely certain of our own existence? This question, seemingly trivial at first glance, actually lies at the heart of profound philosophical disagreements, dividing thinkers into those who seek this certainty in immediate experience and those who see its origins in the rational structure of thought. The problem is not whether we exist but how we know this and what makes this knowledge indubitable.

René Descartes, as is well known, began his philosophical journey with radical doubt, striving to find an unshakable foundation for all knowledge. He doubted everything that could be questioned: the senses, the external world, even the existence of a deceiving God. However, in this process, he discovered something that seemed to escape any doubt: the very act of doubting. If I doubt, then I think, and if I think, then I exist. This famous "Cogito, ergo sum" ("I think, therefore I am") became for Descartes the first indubitable truth [Descartes et al., 2013]. For him, certainty in one's own existence stemmed from the rational obviousness of this conclusion, from the clarity and distinctness of the idea that could not be false as long as it was thought. However, as J. Forsman notes, even for Descartes, "I exist" could not become a starting point for a "long and stable science" without knowledge of the existence of a non-deceptive God [Forsman, 2019]. Without divine guarantee, even clarity and distinctness could be deceptive.

A different position is held by Alexander Billon, who argues that certainty in one's own existence arises from the phenomenal character of experience. He writes: I can claim to be certain only of my experiences, and this certainty, like certainty in my own existence, arises from their phenomenal character [Billon, 2014]. Here the emphasis shifts from logical inference to the immediate, lived quality of consciousness. My sensations, my feelings, my thoughts—they are, and their being does not require additional rational justification. This is not a deduction but a given.

Rationalist interpretations, on the contrary, insist that certainty in one's own existence is rooted in the rational features of propositional attitudes. Billon explains: According to rationalist interpretations, on the other hand, I can be certain only of some of my propositional attitudes, and this certainty, like certainty in my existence, arises from their rational, not their phenomenal, features [Billon, 2014]. Here it is not about experience as such but about the content of thought, its logical structure, about it representing a statement that can be true or false, and in the case of one's own existence—undoubtedly true.

However, as N.V. Volokhova and M.S. Filippovich show, the individual's experience constantly changes under the influence of social, psychological, and other events, forming what Michael Polanyi called the "personal coefficient" [Volokhova et al., 2022]. His concept of tacit personal knowledge includes knowledge of one's own body, its spatial and temporal orientations. This knowledge, according to Polanyi, is implicit to the person, the individual. He relied on the phenomenology of Maurice Merleau-Ponty, who believed that "there is a logic of the world to which my body in its entirety conforms, and through which things of intercessory significance become possible for us," that is, "the body knows more about the world than the 'I' as a conscious subject" [Volokhova et al., 2022]. Here we see how the phenomenological approach grounds certainty in existence not only in consciousness but also in bodily experience, in direct interaction with the world.

Descartes' problem was that, having proven his own existence, he faced the necessity to justify the existence of the external world. If certainty in one's own "I" arises from thinking, how does one move from this internal experience to external objects? John Sergeant, as Richard Glauser notes, criticized Descartes because if ideas exist, then external objects are unknowable [Glauser, 1988]. Descartes, in his view, could not foresee such an objection since his metaphysics in the "Meditations" aimed to establish both the certainty of the existence of bodies and the reality of scientific knowledge about them.

J.E. Moore, in turn, proposed his famous "proof of the external world" simply by raising his hand and saying, "Here is a hand" [Carter, 2012]. His argument was aimed not so much at convincing skeptics of the existence of the external world but at demonstrating that doubting this question is absurd. Moore believed that knowledge does not always require proof and that immediate perception can be a sufficient basis for certainty. However, as J. Adam Carter notes, many philosophers, including Wright, Pryor, and Neta, express deep doubts about the adequacy of this proof while not being skeptics about the external world [Carter, 2012]. This indicates that the problem of certainty in existence is not reducible to a simple assertion of fact.

If Descartes sought certainty in the rational structure of thought, then phenomenologists such as Merleau-Ponty find it in the immediate, pre-reflective experience of body and consciousness, in their inseparable connection with the world. For them, certainty in one's own existence is not the result of logical inference but rather a fundamental given that precedes any reasoning.

However, even if we accept the phenomenological approach, the question arises: how reliable is this immediate experience? Feelings can deceive, as Descartes himself admitted. Dreams and hallucinations can create the illusion of reality. N.V. Volokhova and M.S. Filippovich note that human cognitive ability is constantly subjected to "attacks" from critical remarks that orient the knower toward the degree of trust in their knowledge [Volokhova et al., 2022]. Critical thought trusts the method of doubt because it assumes that after all the "voluntaristic components of opinion," some residue of knowledge remains untouched, fully determined by objective evidence [Volokhova et al., 2022].

This "residue of knowledge" may be what Descartes called clear and distinct ideas or what phenomenologists call the immediate intuition of essences. But even here there remains tension between the rational demand for justification and the phenomenological given of experience. Certainty in one's own existence turns out not to be a monolithic concept but rather a field of interaction of various approaches, each trying to grasp its essence.

Ultimately, the question of the nature of certainty in one's own existence leads us to understand that this certainty can be subject to distortions. What happens when this basic certainty is disrupted, when a person begins to doubt the reality of their "I" or the surrounding world? This question will be the starting point for our next discussion, where we will examine how pathological states such as depersonalization and Cotard's syndrome affect the understanding of certainty in one's own existence.

How Do Pathological States Such as Depersonalization and Cotard's Syndrome Affect the Understanding of Certainty in One's Own Existence?

In the previous section, we discussed how the nature of certainty in one's own existence oscillates between phenomenological and rational poles. If Descartes, as we recall, sought to cleanse the mind of all opinions to find an indubitable foundation for knowledge, what happens when this very foundation—certainty in one's own existence—is doubted not in a philosophical experiment but in a real pathological state? The study of such abnormal states as depersonalization and Cotard's syndrome offers a unique perspective, allowing us to deepen our understanding of the mechanisms underlying our ordinary sense of self and being.

Patients suffering from acute forms of depersonalization or Cotard's syndrome often express doubts about their own thinking and existence and are sometimes even convinced that they do not exist [Billon, 2014]. This is not merely a philosophical mind game but a profound, agonizing experience that calls into question the very possibility of the rationalist interpretation of cogito. If Descartes claimed that "I think, therefore I am" is an indubitable truth accessible to every thinking subject [Reid et al., 1996], how can we explain cases where a person thinks but doubts their own existence?

Alexander Billon argues that studying these pathological cases of self-doubt allows us to favor the empirical interpretation of cogito [Billon, 2014]. According to this interpretation, certainty in one's own existence arises from the phenomenal and subjective character of our experience. We are certain of our being not because we rationally deduce it from the fact of thinking but because we directly experience our sensations and thoughts. If this immediate experience is disrupted, as happens in depersonalization, then certainty in existence can also falter.

Rationalist interpretations, on the other hand, assume that certainty in existence is rooted in the rational features of self-reflective propositional attitudes [Billon, 2014]. However, as Billon notes, "one can be minimally rational and yet doubt one's thoughts and existence" [Billon, 2014]. This observation undermines the idea that rationality alone is a sufficient condition for certainty in cogito. Patients with Cotard's syndrome, for example, may retain certain cognitive functions but be convinced of their death or the absence of organs, which is a radical denial of their own being.

These pathological states demonstrate that certainty in one's own existence is not exclusively a product of logical inference or abstract thinking. It is deeply rooted in our bodily experience, in the sense of oneself as an acting and perceiving subject. Maurice Merleau-Ponty, for example, emphasized the central role of the body in shaping our perception of the world and ourselves, asserting that the body is our way of being in the world. When this connection is disrupted, as in depersonalization, where a person feels detached from their own body and emotions, the sense of reality of one's own "I" becomes unstable.

Skepticism, as a philosophical position, often regards doubt as a tool for achieving deeper knowledge or ataraxia, as in Pyrrhonism. However, pathological doubt differs from philosophical doubt. The philosophical skeptic usually consciously chooses the position of doubt to critically evaluate their beliefs, whereas a person with depersonalization or Cotard's syndrome does not choose their doubts; they are imposed from within, becoming part of their painful experience. This distinction between voluntary and involuntary doubt is crucial for understanding the nature of certainty.

George Edward Moore, in his famous "Proof of the External World," tried to refute skepticism by simply raising his hands and stating, "Here is one hand, and here is another" [Moore et al., 1993]. His argument was that we have immediate knowledge of the existence of the external world that requires no further proof. However, as James Owen Weatherall notes, Moore's "Proof" is part of a broader anti-skeptical strategy [Weatherall, 2015]. But what if a person cannot be certain even of the existence of their own hands, as happens in some forms of depersonalization? Then Moore's argument loses its persuasiveness.

Ludwig Wittgenstein, commenting on Moore's works, also explored the nature of certainty, arguing that some beliefs are "hinges" and are not subject to doubt in ordinary life [Stroll, 1994]. He spoke of the "framework" within which our language games and beliefs function. Pathological states essentially destroy this framework, making it impossible to accept even the most basic assertions about oneself and the world. This is not merely a refusal of proof but a fundamental disruption of the ability to form such foundational beliefs.

In the context of pathological states such as depersonalization, the individual may experience profound alienation from their thoughts and emotions, perceiving them as foreign or unreal. This emphasizes that certainty in one's own existence is closely connected with the feeling of belonging to one's internal states. If these states are perceived as external or not belonging to the "I," then the "I" itself becomes ghostly.

Cases of Cotard's syndrome, where patients are convinced of their death or non-existence, represent an even more radical denial of one's own being. This is not mere doubt but an active belief in non-existence. Such states challenge not only rationalist but also some empirical interpretations of cogito, since even immediate experience can be distorted to the extent that it denies the very basis of existence.

Pathological states such as depersonalization and Cotard's syndrome serve as powerful empirical confirmation that certainty in one's own existence is not solely a rational construct. It is deeply rooted in our phenomenal experience, in the continuity and integrity of our perception of ourselves and the world. When this integrity is disrupted, even the most fundamental beliefs about one's own being can be destroyed. This forces us to reconsider how fragile our certainty can be and how much depends on the normal functioning of our consciousness and its connection with bodily experience. Understanding these pathologies helps us realize that to achieve certainty and order the world, simple rational inference is insufficient; knowledge purified from distortions is also necessary, allowing us to perceive reality without internal "interference."

What is the Role of Knowledge Purified from Opinions in Achieving Certainty and Ordering the World?

After considering how pathological states such as depersonalization or Cotard's syndrome can undermine the very foundation of certainty in one's own existence, a natural question arises: if our self-perception is so fragile, on what can reliable knowledge of the world be built at all? After all, if even "I exist" can be doubted, what can be said about more complex constructs? Here the idea of knowledge purified from opinions comes to the fore as a tool for ordering the irrationality of the world and achieving truth.

The idea that true knowledge must be free from subjective distortions and biased opinions is not new. Francis Bacon, as noted by N.V. Volokhova and M.S. Filippovich, believed that "the sciences studying cognition and thinking are key to all others, for they contain the 'mental instruments' that give the mind" the ability to overcome "idols"—false notions distorting the perception of reality. These "mental instruments" are precisely the filter that allows separating the grains of truth from the chaff of opinions.

But what exactly does "knowledge purified from opinions" mean? It is not merely the absence of personal preferences but the systematic elimination of all forms of bias, cultural conditioning, and even linguistic traps. Arun Agrawal, for example, criticizes attempts to divide knowledge into "Western" and "indigenous," pointing out that such a dichotomy itself is a simplification that does not account for the "radical heterogeneity" within each category [Agrawal, 1995]. He argues that any world is always also a radical heterogeneity that diverges in a fabric of differences, destroying the original identity [Agrawal, 1995]. This means that even within a single cultural or scientific tradition, knowledge is not monolithic and requires constant critical reflection.

The search for such purified knowledge is often associated with the rationalist tradition, where logic and deduction serve as the main instruments. René Descartes, trying to find an indubitable foundation for knowledge, arrived at his famous "Cogito ergo sum"—"I think, therefore I am." For him, this was the first indubitable knowledge that could not be doubted even by the most radical skepticism. From here, he tried to deduce the existence of God and then the external world. This path demonstrates the aspiration to build a system of knowledge on a foundation absolutely free from subjective opinions and empirical errors.

However, even Descartes faced the problem of transitioning from internal, subjective experience to objective knowledge of the world. How to guarantee that our clear and distinct ideas correspond to reality and are not merely products of our mind? Here the concept of God as a guarantor of truth comes to the rescue, but this is more a metaphysical assumption than pure knowledge purified from opinions. Immanuel Kant, in turn, showed that our knowledge is always limited to the phenomenal world, i.e., the world as it appears to us, not the world of "things in themselves" [Kant, 2000]. We cannot know the essence of things beyond our experience, and this limitation is fundamental for human cognition.

Knowledge purified from opinions does not mean absolute or all-encompassing knowledge. Rather, it is knowledge that has undergone rigorous verification for internal consistency and justification, free from arbitrary assumptions and prejudices. This knowledge, as Volokhova and Filippovich say, "allows ordering the irrationality of the world." Irrationality here is understood not as the absence of logic but as the chaos and uncertainty of empirical experience that needs structuring.

In this context, even doubt and skepticism, which at first glance seem obstacles to certainty, can serve as tools for purifying knowledge. N.V. Volokhova and M.S. Filippovich emphasize that "personal knowledge is formed through doubt and a skeptical attitude toward it, which is one of the most important factors determining social trust relations." Doubt becomes not an end but a beginning of the path to more reliable knowledge, forcing us to critically reconsider our beliefs.

However, as J. Adam Carter notes, even when we rationally doubt something, this does not always mean the absence of knowledge. He refers to the argument that doubting a proposition is compatible with knowing it, provided the doubt is unjustified [Carter, 2012]. For example, if a philosopher convinces us to doubt that the universe has existed for more than five minutes, this does not negate our knowledge that we had breakfast three hours ago. This highlights the distinction between rational, justified doubt and irrational, philosophically induced doubt that cannot undermine fundamental beliefs.

Purifying knowledge from opinions is a continuous process requiring intellectual responsibility. It is not merely passive reception of information but active critical thinking, readiness to question even one's own beliefs. As Volokhova and Filippovich assert, "to take risks is a kind of encouragement to intellectual responsibility for personal knowledge, it is personal trust in which the individual is confident." This trust in oneself is based on the conviction that all arguments and logic confirm the correctness of knowledge.

Ultimately, the role of knowledge purified from opinions is to provide us with a reliable guide in a complex and often unpredictable world. It allows us not only to react to external stimuli but also to actively shape our understanding of reality based on justified principles rather than random impressions or prejudices. However, this process of purification is never complete, as the individual is constantly influenced by various kinds of "idols," which must be reckoned with to avoid the trap of false knowledge. These "idols" become the next point of our reflection.

How Do 'Idols' Influence the Individual and the Process of Achieving True Knowledge?

If in the previous section we spoke of knowledge purified from opinions as a path to certainty, now it is worth asking: what hinders this purification? What distorts our perception and impedes the formation of true knowledge? Francis Bacon once introduced the concept of "idols"—false notions deeply rooted in the human mind that prevent it from adequately perceiving reality. These idols are not merely errors but deeply ingrained distortions affecting the process of cognition and, consequently, our certainty in it.

The individual is constantly under the influence of various kinds of "idols," which must be taken into account to avoid falling into the trap of false knowledge. These idols can be divided into several categories, each distorting our understanding of the world in its own way. For example, "idols of the tribe" are rooted in human nature itself, in the peculiarities of perception and thinking. We tend to see more order and regularity in the world than there actually is or interpret facts to fit our biased views. The human mind, like a distorted mirror, mixes its nature with the nature of things, distorting and disfiguring it.

"Idols of the cave," in turn, are connected with the individual peculiarities of each person: their upbringing, education, habits, and personal experience. Each of us has our "cave," our inner world, which forms a unique but limited perspective. What seems obvious to one may be completely alien to another, since their "caves" refract the light of truth differently. This explains why people, confronted with the same facts, come to completely different conclusions, each of which seems absolutely certain to them.

Next come the "idols of the marketplace"—distortions arising from the inaccuracy and ambiguity of language. The words we use to describe the world often do not correspond to reality but rather reflect commonly accepted but not always correct notions. Language, being a tool of communication, can become a source of delusions when we take words for things themselves and accepted terms for true concepts. As Ludwig Wittgenstein noted, the limits of my language mean the limits of my world, and these limits can be quite deceptive.

Finally, "idols of the theater" are false doctrines and philosophical systems that, like theatrical productions, create illusory worlds and lead the mind away from true knowledge. These systems, based on authority or speculative constructions, are often accepted on faith without proper critical examination. They form a kind of intellectual "scripts" according to which we think, not noticing that these scripts may be far from reality. An example can be dogmatism, which, according to David Hume, hinders free inquiry and acceptance of new ideas.

The influence of these idols on the individual manifests in that they create false certainty. A person under their sway may be absolutely convinced of the truth of their views, even if they contradict objective reality. This false certainty is especially dangerous because it blocks critical thinking and impedes the search for true knowledge. As J. Adam Carter notes, doubt in a conclusion can be rational even if the proof seems convincing if it cannot convey justification from premises to conclusion [Carter, 2012].

The process of achieving true knowledge requires constant struggle with these idols. It is not merely the accumulation of facts but active purification of the mind from biases and delusions. René Descartes, doubting everything except the fact of his thinking, tried to find an indubitable foundation for knowledge free from any distortions. However, even his approach faced the problem of the external world, indicating the difficulty of complete liberation from the influence of subjective factors.

Immanuel Kant, in turn, showed that our knowledge is limited to the phenomenal world, and metaphysical questions about "things in themselves" remain inaccessible to certain cognition. This means that even with the most thorough purification from idols, there are fundamental limits to human cognition that prevent achieving absolute certainty in all areas. We can strive for truth but will always encounter the boundaries of our understanding.

In the context of modern discussions about knowledge, the question of so-called "indigenous knowledge" becomes especially relevant. Arun Agrawal points to the dilemma faced by proponents of this approach: on the one hand, they emphasize the importance of preserving and using traditional knowledge, and on the other hand, they must acknowledge its difference from Western scientific knowledge [Agrawal, 1995]. This difference often manifests in the fact that traditional systems of thought may be more "closed" and less susceptible to change in the face of contradictory evidence, reminiscent of the influence of "idols of the theater."

Idols not only distort our perception but also shape our certainty, making it false or unjustified. They create barriers on the path to true knowledge, forcing us to accept illusions as reality. Recognizing the existence of these idols and constantly working to overcome them is a necessary step toward forming more reliable and justified certainty, which, however, will always remain partial and subject to critique. This leads us to the need for critical analysis of the very concept of certainty and its limits.

Criticism and Limitations

One of the fundamental limitations in the search for absolute certainty is the inevitable influence of "idols," as described by Francis Bacon. The individual is constantly under the influence of various kinds of "idols," which must be taken into account to avoid falling into the trap of false knowledge. These distortions, whether "idols of the tribe," "cave," "market," or "theater," shape our beliefs and perception of the world often without our awareness. If we could completely rid ourselves of these biases, our knowledge might be more objective and, therefore, more certain. However, since these "idols" are deeply rooted in human nature, language, and culture, their complete elimination seems impossible. This means that any claim to absolute certainty will always be subject to criticism regarding its possible conditioning by these hidden distortions.

Another significant limitation is related to the problem of transitioning from subjective certainty to objective knowledge. Descartes, having reached indubitability in his cogito, faced the necessity to justify the existence of the external world and God to guarantee the truth of his clear and distinct ideas. However, as J. Forsman notes, even for Descartes, "I exist" could not become a starting point for a "long and stable science" without knowledge of the existence of a non-deceptive God [Forsman, 2019]. Had Descartes not introduced the figure of God as a guarantor of truth, his system would have remained closed within subjective experience, unable to provide certainty about the existence of anything outside consciousness. This raises the question of how universal certainty based on purely personal, albeit indubitable, experience can be.

Finally, even within logic, often regarded as a bastion of certainty, there are limits. Logic provides certainty in its conclusions given the truth of premises but does not guarantee the truth of the premises themselves about being. As Christopher Kutz emphasizes, even in the legal system, which strives for clarity and definiteness, there are "peripheries of uncertainty" in the application of terms and concepts [Kutz, 1994]. This means that even with strict rules of inference, the initial data or definitions may be vague, leading to uncertainty in final conclusions.

Absolute certainty in logical constructions is possible only under the condition of absolute certainty in the truth of all initial premises, which in matters of being is often unattainable.

Conclusions

• The search for absolute certainty in philosophy often leads to skepticism or dogmatism rather than a final answer, as every attempt to build an unshakable system of knowledge encounters internal contradictions or external limitations.
• Descartes tried to build a system of knowledge based on the indubitable "I think, therefore I am," but faced the problem of the external world, which required the introduction of metaphysical assumptions such as the existence of a non-deceptive God.
• Kant showed that our knowledge is limited to the phenomenal world, and metaphysical questions about "things in themselves" remain inaccessible to certain cognition, establishing fundamental limits of the human mind.
• Logic, as a formal system, provides certainty in its conclusions given the truth of premises but does not guarantee the truth of the premises themselves about being, highlighting its instrumental rather than ontological character.
• Pathological states such as depersonalization and Cotard's syndrome demonstrate that certainty in one's own existence is not exclusively a rational construct but deeply rooted in phenomenal experience and the integrity of self-perception.
• Knowledge purified from opinions is a necessary condition for ordering the irrationality of the world, but this process is never complete due to the constant influence of "idols" and fundamental limitations of human cognition.
• Can philosophy offer a path to "peace" regarding uncertainty if the very nature of certainty remains a subject of ongoing disputes and reinterpretations?