IB Diploma Programme Philosophy SL (first assessment 2025; current guide). SL students study ONE optional theme from seven (aesthetics, epistemology, ethics, philosophy of religion, philosophy of science, political philosophy, social philosophy) and ONE prescribed text. This handout kits the most-taught themes (ethics and epistemology in depth, the other five compactly) so any school's choice is covered, and teaches the PRESCRIBED TEXT craft: reading a philosophical classic as philosophers do. All worked examples are original.

Must-know for the optional themes and the text:

ETHICS (the most-taught theme): the three classic theories in permanent debate. Consequentialism 结果主义 judges acts by outcomes — utilitarianism (maximise aggregate wellbeing; its power is decision-guidance, its burdens the tyranny-of-the-majority cases and the demand to calculate the uncalculable). Deontology 义务论 judges acts by duty — Kant's categorical imperative (act only on a maxim you could will universal; treat persons as ends) with its burdens the conflict of duties (the inquiring murderer) and rigour's coldness. Virtue ethics 德性伦理学 judges agents (what would the phronimos do?); character is built by habituation; its burden, action-guidance vagueness. The applied debates (euthanasia, lying, capital punishment) are run three ways, which is the paper's favourite shape.

EPISTEMOLOGY: Knowledge 知识 analysed as justified true belief — and Gettier's cases 葛梯尔案例 (the stopped clock: a true belief justified by luck) breaking the definition; responses (no false lemmas, reliabilism, virtue epistemology). The SOURCES of knowledge: Rationalism 唯理论 (some substantive knowledge is a priori — innate or grasped by reason) vs Empiricism 经验论 (all substantive knowledge from experience) with Kant's synthesis (the mind structures experience). SKEPTICISM as the stress-test: the evil demon, the brain in a vat — and what the skeptic forces the theorist to say.

The other five compactly: AESTHETICS — the definition of art (imitation, expression, form; the institutional theory's move) and the aesthetic attitude (disinterested pleasure; Hume's standard of taste against relativism). PHILOSOPHY OF RELIGION: the arguments (ontological, cosmological, teleological) each with their classic objections, and the problem of evil (logical and evidential; the free-will and soul-making replies). PHILOSOPHY OF SCIENCE — induction (Hume's problem), falsification (Popper), the theory-ladenness of observation (Kuhn's paradigms), realism vs anti-realism about science's unobservables. POLITICAL PHILOSOPHY — the state's justification (consent, utility, fairness — the social-contract debate), liberty (negative and positive; Mill's harm principle), justice (Rawls's veil of ignorance against Nozick's entitlement). SOCIAL PHILOSOPHY — the social self (we become selves through others), ideology and alienation (Marx), and oppression lived (Simone de Beauvoir on the second sex: the othering of women as the paradigm).

The text is studied PHILOSOPHICALLY, not literarily: the paper asks for the text's CLAIMS, its ARGUMENTS for them, and the student's CRITIQUE. The fourfold read 四重解读: context (the question the text answers — its historical and dialectical position), CLAIMS (the positions stated, in the text's own terms), ARGUMENTS (the reasoning offered — reconstructed with the core theme's craft: premises, conclusions, suppressed premises), CRITIQUE (objections the student develops and the text's best reply — evaluation, not summary). The classic list runs from Plato's REPUBLIC through Descartes's MEDITATIONS, Hume's ENQUIRIES, Mill's UTILITARIANISM AND LIBERTY, to contemporary prescribed texts — whichever the school chose, the fourfold read is the method.

Worked example. On Descartes's MEDITATION I (if prescribed): the context, defeating skepticism to found knowledge; the claims: sense deception, dreaming, the evil demon as doubt's escalation; the arguments — the deceiver argument reconstructed premise by premise; the critique — the demon hypothesis is not really dubitable (the “hyperbolic doubt” charges science more than common life), and the cogito's reply already assumes what the doubt questions (the “I”). The fourfold read applied once is the pattern for any text.

• Ethics: the three theories stated with their signature burdens; one applied issue run three ways (ethics).
• Epistemology: JTB and Gettier's cases with one response; rationalism vs empiricism with Kant's move; skepticism as stress-test (epistemology).
• Aesthetics: the definition debate and the aesthetic attitude (aesthetics).
• Religion: the three arguments with classic objections; the problem of evil and its replies (religion).
• Science: induction, falsification, paradigms, realism vs anti-realism (science).
• Political: the contract debate; negative and positive liberty with Mill; Rawls vs Nozick (political).
• Social: the social self; Marx's alienation; de Beauvoir's othering (social).
• The fourfold text read — context, claims, arguments, critique — with the worked Meditation I example (text).

Boundary notes: the theme paper asks one essay on the chosen theme; the text paper asks passage-based analysis and evaluation — the fourfold read answers both. All positions cited are the standard canon; the worked analyses are original.