Archive Record · Wisdom Topic
Knowledge & Truth
Explore how we know what is true — from Socratic inquiry and Platonic forms to modern epistemology, critical thinking, and the nature of reality.
A curated topic hub for philosophical approaches to knowledge, truth, and reality — connecting questions of belief, justification, skepticism, and critical thinking across traditions.
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Knowledge & Truth
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Questions for further inquiry
Key Questions
What Is Mary's Room? Philosophy of Mind Explained
A philosophical explanation of Frank Jackson's knowledge argument, the thought experiment of Mary the color scientist who learns what red looks like, and its implications for the philosophy of mind.
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What Is a Philosophical Zombie?
A philosophical zombie is an imaginary being physically and behaviorally identical to a conscious person but with no inner experience. It is the core thought experiment of the mind-body debate.
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What Is Self-Knowledge? Knowing Your Own Mind
Self-knowledge is the special knowledge we have of our own mental states and character. Philosophers debate its privileged access, the transparency of belief, and whether introspection is reliable. Kahneman and Nisbett and Wilson add the empirical challenge.
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What Is the Explanatory Gap?
The explanatory gap is the failure of physical and functional accounts of the brain to explain why there is anything it is like to have an experience — the gap between neural description and subjective feel.
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Correlation vs Causation: Why Association Is Not Proof
An introduction to the distinction between correlation and causation — why association does not establish cause, the errors that follow from confusing them, and how science tests causal claims.
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What Is a Logical Fallacy? The Recurring Errors of Argument
An introduction to logical fallacies — the systematic patterns of defective argument that appear sound — from Aristotle's sophistical refutations to modern informal logic and argumentation theory.
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What Is a Paradigm Shift? How Scientific Revolutions Change Everything
An introduction to paradigm shifts — Thomas Kuhn's account of scientific revolutions in which a community's shared framework of theories and methods is replaced — from Copernicus to relativity and beyond.
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What Is Confirmation Bias? The Hidden Filter on What We Believe
An introduction to confirmation bias — the tendency to seek, interpret, and remember evidence in ways that support what we already believe — from Bacon's idols to the modern cognitive science of motivated reasoning.
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What Is Critical Thinking? The Art of Reasoning Well
An introduction to critical thinking — the disciplined practice of analyzing, evaluating, and improving reasoning — its history, core skills, and why it matters in the age of information.
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What Is Falsification? Popper's Criterion of Science
An introduction to falsification — Karl Popper's thesis that a hypothesis is scientific only if it is testable and falsifiable — its logic, its role as a demarcation criterion, and its limits.
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What Is Logic? The Systematic Study of Valid Reasoning
An introduction to logic as the systematic study of valid inference — what it is, where it came from, and why it matters for reasoning, science, and everyday judgment.
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What Is the Scientific Method? A Systematic Path to Knowledge
An introduction to the scientific method — the disciplined practice of observation, hypothesis, experiment, and revision — from Bacon's experimental philosophy to Popper's falsificationism and Kuhn's account of paradigms.
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What Is the Brain in a Vat?
A philosophical explanation of the brain in a vat thought experiment, a modern skeptical scenario that asks whether you can know you are not just a brain receiving simulated experiences.
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What Is Empiricism?
A philosophical introduction to empiricism — the view that sensory experience rather than reason is the primary source of knowledge — through Locke, Berkeley, and Hume.
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What Is Free Will?
Free will is the capacity of agents to make choices uncoerced by external forces. Philosophers debate its compatibility with determinism and its relationship to moral responsibility.
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What Is Philosophy?
A philosophical examination of what philosophy is, its major branches from metaphysics to ethics, and how the love of wisdom shapes human inquiry.
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What Is the Mind-Body Problem?
The mind-body problem asks how mental states relate to the physical body and brain, challenging philosophers since Descartes to explain the relationship between consciousness and matter.
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What Is the Self?
A philosophical introduction to the self — the persistent subject of experience — through Descartes's thinking substance, Hume's bundle theory, and contemporary theories of personal identity.
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What Is Truth?
A philosophical introduction to truth — the property of beliefs and statements that accurately represent reality — through correspondence, coherence, and pragmatic theories from Aristotle to William James.
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Hume vs Kant — How Do They Differ?
A comparative analysis of Hume's empiricism and Kant's transcendental idealism, examining their disagreement over causation, the synthetic a priori, and the foundations of knowledge.
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What Is Epistemology? The Philosophy of Knowledge
An introduction to epistemology as the branch of philosophy that studies knowledge, examining what knowledge is, how we acquire it, and the limits of what we can know.
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What Is Philosophy of Mind? Consciousness and the Mental
An introduction to the philosophy of mind, examining the mind-body problem, consciousness, mental states, and the major positions from Cartesian dualism to contemporary physicalism.
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What Is Skepticism?
A philosophical introduction to skepticism, tracing the tradition of doubt from ancient Pyrrhonism through Cartesian methodical doubt to Hume's empiricist challenge to certainty.
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Descartes vs Hume — How Do They Compare?
Descartes sought certainty through rationalist doubt and found it in the thinking self; Hume dismantled that confidence through empiricism, arguing that causation and the self are habits of association.
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Exploring Constructivism — How We Build Reality
Constructivism holds that reality as we know it is partly shaped by the mind's own categories — a view rooted in Kant and developed through idealism into contemporary epistemology.
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Exploring Epistemology — The Study of Knowledge
A comprehensive introduction to epistemology, the branch of philosophy that examines the nature, sources, and limits of knowledge.
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Exploring Post-Truth Society — When Emotion Overrides Fact
An examination of post-truth culture, its philosophical roots, and its consequences for knowledge and democracy.
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Exploring Simulation Theory — Are We Living in a Simulation?
An exploration of simulation theory and whether reality is fundamental, drawing on Bostrom, Descartes, and Plato to examine appearance and reality.
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Exploring the Aesthetic Experience
A philosophical exploration of aesthetic experience examining beauty as Form in Plato, disinterested judgment in Kant, and the dissolution of subject and object in Taoist thought.
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Exploring the Gettier Problem — When Justified True Belief Is Not Knowledge
A close examination of Gettier's 1963 challenge to the justified true belief account of knowledge.
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Exploring the Limits of Human Knowledge
From Descartes's doubt to Kant's critical philosophy and Hume's skepticism, the modern tradition has mapped the boundaries of what minds can and cannot know.
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Exploring the Nature of Consciousness
A philosophical exploration of consciousness examining subjective experience, the mind-body problem, and whether first-person awareness can be captured by physical explanation.
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Exploring the Nature of Truth
Truth is the most contested concept in philosophy — correspondence, coherence, and pragmatist accounts each capture part of what we mean when we say a claim is true.
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Exploring the Philosophy of Language
A philosophical exploration of how words mean, how language shapes knowledge, and the relationship between thought and expression from Plato to Hume.
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Exploring the Problem of Other Minds
A philosophical exploration of whether we can know that other people have inner experiences, examining Cartesian skepticism, Humean naturalism, and Buddhist no-self.
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Hegel vs Nietzsche — How Do They Compare?
Hegel saw history as the rational unfolding of spirit toward freedom; Nietzsche rejected such systems as disguised dogmatism and argued that values are created through individual overcoming.
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How to Distinguish Fact from Opinion?
A practical guide to separating verifiable facts from subjective opinions using evidence, language, and context.
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How to Evaluate Source Credibility?
A systematic framework for assessing the trustworthiness of information sources across academic and online contexts.
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How to Face Reality?
Facing reality requires the courage to see things as they are rather than as we wish them to be — Stoic practice cultivates clear perception, Platonic thought distinguishes appearance from reality, and practical wisdom guides the judgment of what can and cannot be changed.
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How to Find Beauty in Life?
A philosophical guide to recognizing beauty through Platonic ascent, Aristotelian observation, Stoic attention, and Nietzschean creation — from everyday experience to art.
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How to Find Truth
A comparative exploration of truth-seeking across Platonic dialectic, Buddhist insight, and scientific inquiry, examining the methods and dispositions that genuine inquiry demands.
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How to Question Your Assumptions
Assumptions are the invisible scaffolding of thought — questioning them is the discipline that separates genuine inquiry from self-confirmation.
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How to Recognize Cognitive Bias — A Philosophical Approach
Cognitive biases are systematic distortions of judgment that philosophy has studied for millennia — here is how to spot and counter them using tools from Hume, Descartes, and Aristotle.
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How to Seek Wisdom, Not Just Knowledge
Wisdom is not the accumulation of facts but the cultivated capacity to live well, judge soundly, and know what knowledge is worth having — here is how the great traditions pursued it.
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How to Think Critically About Information?
A systematic approach to evaluating information using Socratic questioning, logical analysis, and disciplined skepticism.
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Materialism vs Idealism — What Is the Nature of Reality?
Materialism holds that reality is fundamentally physical, while idealism holds that reality is fundamentally mental — the central ontological disagreement of philosophy.
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Plato vs Nietzsche
A philosophical comparison of Plato and Nietzsche — examining their opposing views on truth, beauty, meaning, and the task of philosophy.
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Rationalism vs Empiricism — How Do We Acquire Knowledge?
A comparison of rationalism and empiricism, their central disagreement, and Kant's attempt to synthesize them.
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Truth vs Belief — The Philosophical Distinction
Truth is about how the world is; belief is about how the mind represents it — conflating the two has been the source of philosophical error for millennia.
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What Is the Coherence Theory of Truth?
A proposition is true when it coheres with a system of mutually supporting beliefs.
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What Is the Correspondence Theory of Truth?
A proposition is true when it accurately corresponds to the facts of reality.
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What Is Determinism?
Determinism is the thesis that every event is fixed by prior causes — a view that has shaped debates about freedom, responsibility, and the nature of reality since antiquity.
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What Is Epistemic Humility?
Epistemic humility is the recognition that one's beliefs are fallible and one's access to truth is limited — a virtue with roots in Socratic philosophy, Humean skepticism, and Kantian critical philosophy.
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What Is Intellectual Humility?
Intellectual humility is the recognition of the limits of one's knowledge and the openness to revise beliefs in light of new evidence — a virtue with roots in Socratic philosophy and contemporary epistemology.
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What Is Justified True Belief?
The justified true belief account holds that knowledge is belief that is both true and backed by adequate reasons — a definition that shaped epistemology for over two thousand years.
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What Is Metaphysics?
Metaphysics is the study of reality at its most fundamental level, asking what exists, what it is to be, and what structures underlie all phenomena.
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What Is the Pragmatic Theory of Truth?
A proposition is true when belief in it proves useful and successful in practice.
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What Is Reality?
A comparative philosophical introduction to reality through Plato's Forms, Aristotle's substances, the Taoist Tao, and the Stoic logos — from eternal ideas to the rational order of nature.
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What Is Solipsism?
Solipsism is the philosophical position that only one's own mind is certain to exist — the extreme form of skepticism that challenges every assumption about an external world.
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What Is the Philosopher's Task?
The philosopher's task is not to accumulate opinions but to examine assumptions, clarify concepts, and pursue understanding — Socrates called it the examined life, the Buddha called it inquiry into the nature of suffering, and Kant called it the critique of reason.
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What Is Beauty?
A comparative philosophical introduction to beauty through Plato, Aristotle, Stoicism, and Nietzsche — from Forms and harmony to art, creation, and life affirmation.
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What Is Knowledge?
A comparative philosophical introduction to knowledge through Plato, Aristotle, Stoicism, and existentialism — from justified true belief to critical self-examination.
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Ideas that shape the theme
Wisdom Concepts
Curiosity
Curiosity is the active desire to know what is unknown — the restless intellectual appetite that drives inquiry, exploration, and the pursuit of understanding for its own sake, beyond any immediate practical need.
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Doubt: Meaning, Philosophy & Wisdom
Doubt is the philosophical practice of withholding assent from beliefs that lack sufficient justification, serving as the engine of critical inquiry, the foundation of methodical skepticism, and the guardian of intellectual honesty throughout the history of thought.
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Imagination: Meaning, Philosophy & Wisdom
Imagination is the mind's capacity to form images, concepts, and ideas beyond immediate sensory experience, serving as a bridge between perception, knowledge, and creative insight throughout the history of philosophy.
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Rationality
A philosophical exploration of rationality as the capacity for reason-based thought and action, from Greek logos through Kantian reason to contemporary debates about bounded rationality.
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Skepticism
A philosophical exploration of skepticism as the practice of suspending judgment, from ancient Pyrrhonism through Descartes' methodical doubt and Hume's inductive skepticism to contemporary epistemology.
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Wonder: Meaning, Philosophy & Wisdom
Wonder is the deep sense of awe and perplexity that arises when the mind encounters what is strange, beautiful, or unexplained, and it has been identified since antiquity as the origin of philosophy itself and the beginning of wisdom.
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Reality
A comparative introduction to reality through Plato's Forms, Aristotle's substance, Taoist way, and Stoic logos — from appearance to what truly is.
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Reason
A comparative philosophical exploration of reason as the distinctive human faculty through Greek philosophy, Stoic living, and Kantian critical examination.
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Beauty
A comparative introduction to beauty as order, harmony, form, and life-affirming creation across Greek, Stoic, and existential philosophical traditions.
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Knowledge
A comparative introduction to knowledge as justified understanding, distinguishing it from opinion, information, and wisdom across Greek, Stoic, and existential traditions.
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Truth
A comparative introduction to truth as correspondence, coherence, and practical understanding across Greek, Stoic, and existential philosophy.
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Voices in the archive
Important Thinkers
Thomas Nagel: The View from Nowhere & Philosophy
Explore Thomas Nagel's philosophy of mind, the subjective character of experience, what it is like to be a bat, the view from nowhere, and his critique of physicalism.
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Daniel Kahneman: Two Systems, the Remembering Self, and Happiness
An evidence-led introduction to Daniel Kahneman, the Nobel-winning psychologist who showed that the mind runs on two systems, that we judge lives by moments, and that what we remember of experience is not what we lived.
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Daniel Dennett: Philosophy, Quotes & Legacy
Explore Daniel Dennett's philosophy of mind, his intentional stance theory, multiple drafts model of consciousness, and bold defense of Darwinian naturalism.
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David Chalmers: Philosophy, Quotes & Legacy
Discover David Chalmers' philosophy, the hard problem of consciousness, philosophical zombies, and his case for panpsychism in the philosophy of mind.
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Thomas Kuhn: Philosophy, Quotes & Legacy
Explore Thomas Kuhn's philosophy of science including paradigm shifts, normal science, and scientific revolutions that transformed how we understand knowledge.
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Augustine of Hippo
Augustine of Hippo (354-430) was a North African bishop and philosopher whose synthesis of Christian theology with Greek philosophy shaped Western thought for over a millennium.
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Bertrand Russell
A comprehensive introduction to Bertrand Russell, the British philosopher who co-authored Principia Mathematica, developed the theory of descriptions, and shaped the analytic tradition through his work on logic, language, and knowledge.
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Edmund Husserl
Austrian-German philosopher who founded phenomenology, the rigorous study of consciousness and lived experience, transforming twentieth-century philosophy through intentionality and the phenomenological method.
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Karl Popper
Karl Popper (1902-1994) was an Austrian-British philosopher who transformed the philosophy of science through falsificationism and defended the open society against totalitarianism.
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Gottfried Wilhelm Leibniz
German philosopher and mathematician whose doctrine of monads, principle of sufficient reason, and theodicy made him the last great rationalist and a founder of modern logic.
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Ludwig Wittgenstein
Austrian-British philosopher who transformed twentieth-century thought through his work on language, logic, and the limits of what can be said.
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John Locke
An introduction to John Locke as the founder of British empiricism and liberal political philosophy, whose theories of mind, rights, and government shaped the modern world.
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Karl Marx
A comprehensive introduction to Karl Marx as a philosopher of historical materialism, class struggle, and alienation, whose critique of capitalism reshaped modern thought.
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René Descartes
French philosopher and mathematician whose method of systematic doubt established a new foundation for knowledge and inaugurated modern philosophy.
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David Hume
Scottish philosopher whose empiricist investigation of knowledge, causation, and morality reshaped modern philosophy and provoked Kant's critical turn.
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Immanuel Kant
German philosopher whose critical philosophy revolutionized epistemology, ethics, and aesthetics through systematic accounts of reason, experience, and moral duty.
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Baruch Spinoza
Dutch philosopher whose rationalist metaphysics, ethical theory, and account of the emotions influenced later thought on freedom, determinism, and the intellectual love of God.
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Plato
An introduction to Plato's dialogues, philosophical method, and enduring investigations of justice, knowledge, education, and the good.
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Socrates
A historically careful introduction to Socrates, the Athenian philosopher portrayed in Plato and Xenophon as a practitioner of ethical inquiry.
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Primary and enduring texts
Classic Books
Discourse on the Method
A philosophical guide to Descartes's Discourse on the Method, examining its four rules of reasoning, methodical doubt, and the foundations of rationalist philosophy.
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Critique of Pure Reason
Immanuel Kant's 1781 investigation of the limits and conditions of human knowledge, establishing the critical philosophy that reshaped modern thought.
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Nicomachean Ethics
An evidence-led guide to Aristotle's inquiry into flourishing, virtue, friendship, practical wisdom, and the good human life.
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Republic
An archive entry on Plato's Republic, its inquiry into justice, education, political order, knowledge, and the examined life.
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Traditions for comparison
Related Philosophies
Idealism
An introduction to idealism, the philosophical view that reality is fundamentally mental — from Plato's Forms and Berkeley's immaterialism to German idealism and contemporary panpsychism-adjacent positions.
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Philosophy of Logic
An introduction to the philosophy of logic — the study of the nature, scope, and foundations of logical truth, logical consequence, and the very idea of a system of valid inference.
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Analytic Philosophy
An introduction to analytic philosophy, the tradition emphasizing logical analysis, language, and clarity, from Frege and Russell through Wittgenstein and Quine to the contemporary divide.
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Metaphysics
An introduction to metaphysics as the branch of philosophy that studies the nature of reality, existence, and being, from Aristotle through medieval scholasticism to contemporary analytic philosophy.
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Philosophy of Language
An introduction to the philosophy of language, tracing how thinkers from Frege and Russell through Wittgenstein and beyond analyzed meaning, reference, truth conditions, and the practical use of words in communication.
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Philosophy of Religion
Philosophy of religion is the philosophical examination of religious claims, concepts, and practices, including arguments for God's existence, the problem of evil, and the nature of faith.
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Philosophy of Science
An introduction to the philosophy of science, tracing how thinkers from the logical positivists through Popper, Kuhn, and Lakatos analyzed scientific method, theory change, the demarcation problem, and the nature of scientific knowledge.
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Political Philosophy
An introduction to political philosophy, the study of justice, authority, rights, and the state, from Plato's Republic through the social contract tradition to Rawls and contemporary debates.
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Epistemology
An introduction to epistemology as the philosophical study of knowledge, examining justification, belief, truth, skepticism, and the limits of human understanding from Descartes through contemporary debates.
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Philosophy of Mind
An introduction to the philosophy of mind, examining consciousness, mental states, the mind-body problem, dualism, physicalism, and functionalism from Descartes to contemporary cognitive science.
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Empiricism
An introduction to empiricism as the philosophical tradition that grounds knowledge in sensory experience, from Locke and Berkeley through Hume to logical positivism.
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Phenomenology
An introduction to phenomenology as the philosophical method of describing lived experience, from Husserl through Heidegger and Merleau-Ponty to contemporary practice.
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Pragmatism
An introduction to pragmatism as the American philosophical tradition that evaluates ideas by their practical consequences, from Peirce through James and Dewey to Rorty.
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Rationalism
An introduction to rationalism as the philosophical tradition that privileges reason as the primary source of knowledge, from Descartes through Spinoza and Leibniz to Kant.
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Greek Philosophy
An evidence-led introduction to ancient Greek philosophy, from Socratic inquiry to Plato, Aristotle, and enduring debates about virtue, reason, and knowledge.
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Stoicism
An evidence-led introduction to Stoicism, its Greek origins, Roman development, central virtues, and continuing influence.
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Quotation archive
Wisdom Passages
“The unexamined life is not worth living for a human being.”
“The Dao that can be told is not the eternal Dao; the name that can be named is not the eternal name.”
“Hitherto it has been assumed that all our knowledge must conform to objects. But all attempts to extend our knowledge of objects by establishing something in regard to them a priori, by means of concepts, have, on this supposition, ended in failure. We must therefore make trial whether we may not be more successful in the tasks of metaphysics, if we suppose that objects must conform to our knowledge.”
“All phenomena are preceded by the mind. The mind is their master; they are produced by the mind. If one speaks or acts with a corrupted mind, suffering follows, as the wheel of the cart follows the ox's hoof.”
“Some things are within our power, while others are not. Within our power are opinion, motivation, desire, aversion, and, in a word, whatever is of our own doing; not within our power are our body, our property, reputation, office, and, in a word, whatever is not of our own doing.”
“Imagination is more important than knowledge. For knowledge is limited, while imagination embraces the entire world.”
“The important thing is not to stop questioning. Curiosity has its own reason for existing.”
“Everything should be made as simple as possible, but not simpler.”
“The most beautiful thing we can experience is the mysterious. It is the source of all true art and science.”
“Sapere aude! Have the courage to use your own understanding.”
“Two things fill the mind with ever new and increasing admiration and awe: the starry heavens above me and the moral law within me.”
“The unexamined life is not worth living for a human being.”
“And now, I said, let me show in a figure how far our nature is enlightened or unenlightened: Behold! human beings living in an underground den, and at the entrance a fire.”
“Emotion, which is suffering, ceases to be suffering as soon as we form a clear and precise picture of it.”
“The natural law is nothing else than the rational creature's participation of the eternal law.”
“I will suppose therefore that not God, who is supremely good and the fountain of truth, but some evil genius not less powerful than deceitful, has employed his whole energies in deceiving me.”
“Custom, then, is the great guide of human life. It is that principle alone, which renders our experience useful to us, and makes us expect, for the future, a similar train of events with those which have appeared in the past.”
“True ideas are those that we can assimilate, validate, corroborate and verify. False ideas are those that we cannot.”
“That eternal and infinite being we call God, or Nature, acts from the same necessity from which it exists.”
“Gradually it has become clear to me what every great philosophy so far has been: namely, the personal confession of its author and a kind of involuntary and unconscious memoir; also that the moral (or immoral) intentions in every philosophy constituted the real germ of life from which the whole plant had grown.”
“Human reason has this peculiar fate that in one species of its knowledge it is burdened by questions which, as prescribed by the very nature of reason itself, it is not able to ignore, but which, as transcending all its powers, it is also not able to answer.”
“Custom, then, is the great guide of human life.”
“A free man thinks of nothing less than of death, and his wisdom is a meditation on life, not on death.”
“The soul of the philosopher thinks that it must not resist this deliverance, and so it cultivates calmness and joy and smooths the way for the deliverer.”
“Education isn't what some people declare it to be, namely, the putting of knowledge into souls that lack it, like putting sight into blind eyes. Rather, the power to learn is present in everyone's soul, and the instrument with which each learns is like an eye that cannot be turned from darkness to light without the whole body being turned.”
“The blame is his who chooses. God is blameless.”
“Beauty itself is alone with itself, single in nature, while all the beautiful things share in it in such a way that when others come to be or pass away, it neither grows nor diminishes nor suffers any change.”
“All men by nature desire to know.”
“The heart has its reasons, which reason does not know.”
“The things that appear to us, whether they appear truly or falsely, are things that are given.”
“If we are to have knowledge of the world, we must have some beliefs that are not derived from other beliefs.”
“Inquiry is the controlled or directed transformation of an indeterminate situation into one that is determinate.”
“The only principle that does not inhibit progress is: anything goes.”
“Epistemic injustice is done to someone in their capacity as a knower.”
“Hermeneutical injustice comes about when there is a gap in collective interpretive resources.”
“The following two conditions are not sufficient for S to know that P: (i) P is true, (ii) S believes that P, and (iii) S is justified in believing that P.”
“What justifies a belief is not another belief but the reliability of the process that produced it.”
“Feminist epistemology questions the very standards by which knowledge claims are evaluated.”
“A wise man proportions his belief to the evidence.”
“Truth happens to an idea. It becomes true, is made true by events.”
“All knowledge begins with experience, but not all knowledge arises out of experience.”
“Thoughts without content are empty, intuitions without concepts are blind.”
“Normal science means research firmly based upon one or more past scientific achievements.”
“The actual hard core of a research programme need not be tested in isolation.”
“All ideas come from sensation or reflection.”
“Knowledge is the perception of the agreement or disagreement of two ideas.”
“The fixation of belief is the sole object of inquiry.”
“Consider what effects, which might conceivably have practical bearings, we conceive the object of our conception to have. Then, our conception of these effects is the whole of our conception of the object.”
“Knowledge which is acquired under compulsion obtains no hold on the mind.”
“The beginning of truth is to know the truth about ourselves.”
“Truth is not manifest. The truth in science may never be found.”
“The totality of our so-called knowledge or beliefs, from the most casual matters of geography and history to the profoundest laws of atomic physics, is a man-made fabric which impinges upon experience only along the edges.”
“Each of us is a web of belief, at the center of which is the self.”
“The question what is to be taken as real turns out to be a question of degree.”
“We are acquainted with anything, when we are directly aware of it, without the intermediary of any process of inference or any knowledge of truths.”
“Our judgments are correct when our faculties function well in the right environment.”
“A belief is apt if it is true because adroit, because produced by a competent faculty.”
“Science aims to give us theories which are empirically adequate; and acceptance of a theory involves as belief only that it is empirically adequate.”
“The distinction between observable and unobservable entities is not a philosophical distinction but a scientific one.”
“Certainty is as it were a tone in which I utter sentences. A tone I cannot fully describe.”
“The meaning of a word is its use in the language.”
“In the case of all things which have several parts and in which the totality is not, as it were, a mere heap, but the whole is something beside the parts, there is a cause of it.”
“Cogito ergo sum (I think, therefore I am).”
“I think it's much more interesting to live not knowing than to have answers which might be wrong.”
“The supposition, that the future resembles the past, is not founded on arguments of any kind, but is derived entirely from habit, by which we are determined to expect for the future the same train of objects, to which we have been accustomed.”
“Reason must approach nature in order to be taught by it, but not in the character of a pupil who listens to everything the teacher likes to say, but of an appointed judge who compels the witnesses to answer questions which he has himself formulated.”
“The transition from a paradigm in crisis to a new one from which a new tradition of normal science can emerge is far from a cumulative process, one achieved by an articulation or extension of the old paradigm. Rather it is a reconstruction of the field from new fundamentals.”
“If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind.”
“Logic, I should maintain, must no more admit a unicorn than zoology can; for logic is concerned with the real world just as truly as zoology, though with its more abstract and general features.”
“Extraordinary claims require extraordinary evidence.”
“I propose to consider the question, 'Can machines think?'”
“For a large class of cases — though not for all — in which we employ the word 'meaning' it can be defined thus: the meaning of a word is its use in the language.”
“Wovon man nicht sprechen kann, darüber muss man schweigen. (Whereof one cannot speak, thereof one must be silent.)”
“Therefore, Ananda, be a lamp unto yourselves, be a refuge unto yourselves; take no other refuge. Hold to the Dhamma as a lamp, hold to the Dhamma as a refuge.”
“Form is emptiness, emptiness is form. Form is no other than emptiness, emptiness is no other than form. The same is true of feelings, perceptions, mental formations, and consciousness.”
“The minnows swim out so freely! That is the joy of fish. ... You ask me how I know that the fish are happy — and you know that I know it, because I know it from right here above the Hao.”
“The trouble with Eichmann was precisely that so many were like him, and that the many were neither perverted nor sadistic, that they were, and still are, terribly and terrifyingly normal.”
“Power and knowledge directly imply one another; there is no power relation without the correlative constitution of a field of knowledge, nor any knowledge that does not presuppose and constitute at the same time power relations.”
“Communicative action is a type of interaction in which the participants coordinate their pursuit of their individual goals through communicatively achieved agreement.”
“The right and the good are the right and the good because God has willed them: the reason does not discover the moral order as an independent fact but as the order that the divine will has established.”
“That than which nothing greater can be conceived.”
“Differance is not neither a word nor a concept.”
“The world is not what I think, but what I live through.”
“A theory that is not refutable by any conceivable event is non-scientific. Irrefutability is not a virtue of a theory, but a vice.”
“Knowledge without action is wastefulness and action without knowledge is foolishness.”
“The gifts of grace are added to nature in such a way that they do not destroy it, but rather perfect it. So the light of faith, which is gratuitously infused, does not destroy the light of natural reason.”
“If the activity of philosophy is nothing more than the study of existing beings and reflection on them as indications of the Artisan — I mean, since they are signs of the Artisan — then the Law invites us and urges us to undertake this reflection.”
“One of us must imagine himself as created all at once, fully formed and perfect, but with his vision veiled from the perception of external things: not seeing, not hearing, not touching — suspended in the air, falling, with no air resistance to make him feel anything. Would he affirm the existence of his own self? He would not doubt that he exists.”
“The principle of verification is supposed to furnish a criterion by which it can be determined whether or not a sentence is literally meaningful.”
“Simulation is no longer that of a territory, a referential being or a substance. It is the generation by models of a real without origin or reality: a hyperreal.”
“Pure duration is the form which the succession of our conscious states assumes when our ego lets itself live, when it refrains from separating its present state from its former states.”
“The cylinder rolls and the cone spins: the same push, different natures — and so it is with fate and the person: the occasion is given, and the response is the nature's own. The responsibility is the response.”
“Logic is the science of argument and the foundation of the philosophical life: the person who cannot reason cannot live well, for every act of the wise person is an act of reasoning.”
“The good is a disposition of the soul, and it is the same as virtue; the virtue of the soul is what is genuinely good, and everything else is indifferent.”
“The logos is the artisan fire, working methodically toward the generation of the cosmos: the fire that does not merely burn but shapes, and the reason that is the heart of the world.”
“Truth is not a property, truth is not a relation, truth is not a behavior. What then is truth? Coherence is the key.”
“My thesis is that anarchism helps to achieve progress in any one of the senses one cares to choose. Even a law-and-order science will succeed only if occasional and temporary steps into anarchism are allowed. The only principle that does not inhibit progress is: anything goes.”
“Beauty is no quality in things themselves: it exists merely in the mind which contemplates them; and each mind perceives a different beauty.”
“Observe constantly that all things take place by change, and accustom yourself to consider that the nature of the universe loves nothing so much as to change the things which are and to make new things like them. For everything that exists is in a manner the seed of that which will be.”
“The sun shines on all without distinction, giving light to the world without asking what it illumines: be like the sun — the reason within you is the light that illumines the life, without distinction and without reserve.”
“I am my body, at least wholly in so far as I am experience, and in so far as experience takes place, the body is the unperceived that is perceived in every perception.”
“The judgment is the target: the Stoic correction of the judgment is the ancestor of the cognitive therapy, and the person who has learned to examine the thoughts has learned the beginning of the freedom.”
“The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it.”
“The books are the companions of the wise: the conversation with the great minds never ends, and the person who reads the wise has gathered the friends that no time and no fortune can take away.”
“Reason is the distinctive gift of the human being: the life lived by reason is the life in agreement with nature, and the person who has perfected the reason has perfected the nature.”
“What is tolerance? It is the consequence of humanity. We are all formed of frailty and error; let us pardon reciprocally each other's folly. That is the first principle of natural law.”
“Consciousness, then, does not appear to itself chopped up in bits. Such words as 'chain' or 'train' do not describe it fitly as it presents itself in the first instance. It is nothing jointed; it flows. A 'river' or a 'stream' are the metaphors by which it is most naturally described.”
“He intends only his own gain, and he is in this, as in many other cases, led by an invisible hand to promote an end which was no part of his intention.”
“The soul is the first actuality of a natural body that has life potentially.”
“Why should physical processing give rise to a rich inner life at all? It seems objectively unreasonable that it should, and yet it does.”
“Consciousness is a physical, biological phenomenon that is also, at the same time, a sort of user-illusion.”
“It is natural, now, to think of there being connected with a sign (name, combination of words, letter), besides that to which the sign refers, which may be called the reference of the sign, also what I should like to call the sense of the sign, wherein the mode of presentation is contained.”
“Let's call something a rigid designator if in every possible world it designates the same object, a nonrigid or accidental designator if that is not the case.”
“Though the world does not change with a change of paradigm, the scientist afterward works in a different world.”
“There are never two beings in nature which are perfectly alike, and in which it is impossible to discover an internal difference.”
“If I am asked, 'What is good?' my answer is that good is good, and that is the end of the matter.”
“To be is to be the value of a variable.”
“Syntax is not sufficient for semantics. The point is you can't get semantics from syntax alone.”
“"Ipsa scientia potestas est." (Knowledge itself is power.)”
“No man ever steps in the same river twice, for it is not the same river and he is not the same man.”
“We live in the best of all possible worlds.”
“The One is all things and no one of them; the source of all things is not all things; and yet it is all things in a transcendental sense.”
“The limits of my language mean the limits of my world.”
“Whereof one cannot speak, thereof one must be silent.”
“Let us then suppose the mind to be, as we say, white paper, void of all characters, without any ideas. How comes it to be furnished? Whence comes it by that vast store? Whence has it all the materials of reason and knowledge? To this I answer, in one word, from experience.”
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