Philosophy 101: The Great Thinkers & Their Ideas

The Socratic method, or elenchus, uses critical questioning to reveal contradictions and refine beliefs through four steps—questioning, counterexample, refinement, and conclusion—shaping modern law and philosophy.

Unpack Socrates' legacy, preserved through Plato's dialogues and shifting philosophy from cosmology to ethics and the good life, through self-examination, questioning values, and the belief that ignorance leads to wrongdoing.

Explore how Plato, influenced by Socrates, critiques democracy and writes dialogues on ethics, politics, knowledge, and reality. Explore the world of forms, the cave allegory, and philosopher kings.

Trace Aristotle's life from studying at Plato's Academy and his views on the theory of forms to founding the Lyceum, tutoring Alexander the Great, and exile from Athens.

Aristotle develops logic, syllogism, and laws of thought, then explores metaphysics as the first philosophy, explains four causes, and links virtue and happiness to the golden mean and government.

Francis Bacon revolutionized natural philosophy and scientific methodology during the Renaissance, challenging Aristotelian methods in favor of the rising humanistic movement.

Explore bacon's emphasis on observation and experimentation as the foundation of natural philosophy and science, identify his four idols—tribe, cave, marketplace, theatre—and explain his inductive method.

David Hume, a key figure in western philosophy, wrote A Treatise of Human Nature after Edinburgh and France, but his reputation as a skeptic and atheist hindered university positions.

Explore Hume's empiricist view that knowledge comes from experience and ideas arise from impressions. Examine matters of fact require experience and morality, shaped by direct and indirect passions and sympathy.

Thomas Aquinas embraced a life of service and, after studying Aristotle, joined the Dominican Order. He taught that reason and faith coexist and that all knowledge comes from God.

Explore Aquinas's five ways for God's existence from the unmoved mover to design, and his ethics with Aristotle, outlining the four cardinal virtues: justice, prudence, courage, temperance.

Jean-Jacques Rousseau's life stories, from early hardship in Geneva to becoming a central Enlightenment figure, frame his ideas on freedom, morality, and the state of nature that influenced revolutions.

Rousseau links natural and unnatural inequality to self-preservation, pity, and perfectibility, showing how socialization breeds reason and the division of private property and labor that yields oppression and false equality.

Rousseau argues that civil society restricts natural freedom, and the sovereign's legitimacy rests on the consent of the governed, with the general will shaping laws.

Examine Immanuel Kant's transcendental idealism, distinguishing phenomena from noumena, and how the mind structures experience to yield synthetic a priori knowledge and universal moral laws grounded in intentions.

Explore utilitarianism as a moral theory that judges actions by consequences, tracing Bentham's felicific calculus and act utilitarianism to Mill's emphasis on higher versus lower pleasures and the greatest number.

Compare act and rule utilitarianism, explain morality based on outcomes and happiness, and examine criticisms, including torturing an innocent person to prevent a war and uncertain consequences.

John Locke outlines natural rights, property through labor, and knowledge from experience, detailing primary and secondary qualities and the blank state. His works shape modern democracy and political thought.

Empiricism holds knowledge comes from sensory experience, shaping epistemology. Rationalism claims reason and innate ideas underlie knowledge; Locke rejects innate knowledge, and later forms like logical positivism dismiss unverifiable beliefs.

Hegel's dialectic drives history through thesis, antithesis, synthesis, linking social spirit to the modern state, recognition in master-slave dynamics, and ethics guiding politics, religion, and society.

Trace Descartes's shift from sensory doubt to reason, outlining the method of doubt, the idea "I think, therefore I am," and the move toward universal mathematical reasoning in philosophy.

Explore Descartes' quest for self-evident truths by linking thoughts, perceptions, and imagination to knowledge of God, the ontological argument, and Cartesian dualism of mind and body.

Thomas Hobbes argues that only a strong central authority can prevent anarchy, advocating an absolute monarchy established through a social contract to ensure peace and order.

Explore the linguistic turn linking language, cognition, and reality, Hobbes’s meaning from structure and semantics, and syntactic and semantic trees, alongside innatism, behaviorism, and hypothesis testing in language learning.

Jean-Paul Sartre pioneers existentialism by developing his ideas on freedom and self-definition, writing Nausea (1938) and Being and Nothingness (1943), and engaging publicly on socialism and France's colonisation of Algeria.

Explore Sartre's existential view that humans are beings for themselves who define themselves through actions, confront fixed essences, embrace radical freedom with personal responsibility, and reject universal ethical rules.

Friedrich Nietzsche endures early loss, studies philology in Bonn and Leipzig, befriends Richard Wagner, and later publishes the birth of tragedy before resigning from Basel.

Friedrich Nietzsche declares god is dead, warns against nihilism, and seeks meaning through the will to power, self-overcoming, and mastery. He presents the overman and tests affirmation via eternal recurrence.

Explore Ludwig Wittgenstein's move from early logic to a fluid, use-based theory of language, introducing language games and forms of life that define meaning through everyday use.

Arthur Schopenhauer developed a pessimistic outlook after witnessing poverty, wrote the world as will and representation and fourfold root of the principle of sufficient reason, and debated Hegel in Berlin.

Explore Schopenhauer's pessimism, where reality is a representation shaped by the mind, the will drives endless suffering, and art, especially music, offers temporary relief through compassion.

Explore Karl Marx's development of historical materialism and his collaboration with Engels, tracing his life from Prussia to London and works like the Communist Manifesto and Das Kapital.

Marx argues that material conditions shape society and drive history through economic systems and class struggle. Marx links alienation, labor value, and exploitation under capitalism, predicting a move to communism.

Explore Heidegger's being in time, focusing on Dasein, being-in-the-world, and the three modes of being where tools gain meaning within projects. Consider the turn, technology versus poetry in revealing being.

Voltaire, a leading enlightenment thinker, shaped philosophy, literature, and science. He championed religious freedom and separation of church and state, critiqued superstition, and authored Candide, influenced by England and Locke.

Advocates religious liberty and deism, values reason over faith, treats the Bible as metaphorical, critiques monarchy, aristocracy, and democracy, and champions a constitutional monarchy guided by philosophers and Newtonian science.

Explore Avicenna's influence as a key Islamic Golden Age thinker whose work advanced philosophy, ethics, logic, and medicine, and his ideas on essence, existence, and four faculties of reason.

Bertrand Russell, a logician and philosopher, helped establish analytic philosophy. He promoted logicism in Principia Mathematica and proposed logical atomism to illuminate truth in language, including definite descriptions.

Gottfried Wilhelm Leibniz advances an optimistic rational philosophy, detailing monads, the law of continuity, sufficient reason, identity of indiscernibles, pre-established harmony, and best possible world to reconcile faith and reason.

Spinoza presents a naturalistic view of God and nature, rejects miracles, and separates religion from politics, linking virtue to rational knowledge and self-mastery to harmony with nature.

Explore Eastern philosophy across Asia’s diverse schools in China, India, Korea, and Japan, emphasizing accepting truths, seeking balance, and recognizing the interconnectedness of all things.

Survey orthodox and heterodox Indian philosophy, from Samkhya dualism and Yoga to Nyaya, Vaisheshika, Purva mamasa, and Vedanta, with Upanishadic meditation and Gandhi's ahimsa.

Korean philosophy blends native shamanism with Chinese-influenced Buddhism, Confucianism, and Taoism, shaping ethics, law, and social hierarchy, while Shintoism rises under Japanese rule and Western ideas like Marxism grow.

Japanese philosophy blends Chinese thought, native Shintoism, and Western influences, tracing Zen, Pure Land, Nichiren, Kyoto School, and schools like Soto, Rinzai, and Obaku.

Explore dualism and the mind-body relationship, detailing substance, property, and predicate dualism, Descartes' view, subjective experiences, and arguments for and against mind-body separation.

Explore hedonism as a framework that prioritizes pleasure and the avoidance of pain in well-being. Trace its history from Aristippus to utilitarianism and examine ethical implications.

Explore hard determinism, which asserts universal causation and no free will, and examine objections from choice, drive resistance, and moral responsibility.

Explore the trolley problem's ethical tension between five lives versus one, contrasting consequentialism, utilitarianism, and the doctrine of double effect with self-defense examples.

Realism holds universals exist independently of mind and language, such as redness shared by a red apple and red cherry. It presents extreme realism and Plato's theory of forms.

Explore what it means to choose freely and the moral implications of our choices, comparing compatibilism and incompatibilism, and examining responsibility, determinism, and the question of true freedom.

Explore normative, meta, and applied ethics to understand what makes actions right or wrong, from consequentialism and deontology to virtue ethics, ethics of care, and human rights, abortion, and law.

Review the course's ideas and stay curious as you reflect on philosophy's core questions. Access the PDF with summaries and key points, and share reflections in the discussion.