IB Diploma Programme Philosophy HL (current guide). This topic covers the COMPULSORY CORE THEME in full — Being human — the course's spine: what it is to be human, examined through identity, freedom, personhood and mind–body, with the PHILOSOPHICAL CRAFT (argument analysis, the classic skills) taught alongside. Every study of an optional theme returns to this core; every paper rewards the craft it teaches. The worked examples are original.

Must-know for the core theme:

Philosophy 哲学 proceeds by argument 论证: premises offered in support of a conclusion. The craft the papers test: identify the CONCLUSION and the PREMISES; evaluate the INFERENCE (VALID if the conclusion follows necessarily, whatever the premises' truth; SOUND if valid with true premises — validity is about form, soundness adds truth); and recognise the argument forms: deductive (necessity) and inductive 归纳的 (probability from cases). The classic failures each have names: BEGGING THE QUESTION (the conclusion smuggled into a premise), the STRAW MAN (refuting a weakened copy), the FALSE DILEMMA (two options declared the only ones), the APPEAL TO AUTHORITY (a name where a reason belongs). Philosophical writing is this discipline made visible: a CLAIM, a REASON, an OBJECTION answered: the essay's spine in three moves. The second craft is the thought experiment 思想实验 (philosophy’s laboratory): an imagined case (the ship of Theseus, the teleporter) that isolates a concept by stressing it; the paper asks what the case shows and what it assumes.

Worked example. “Every event has a cause, so my choices have causes, so I am not free.” Identify: P1 every event caused; C1 choices caused; C2 not free. Valid? Only with a suppressed premise — that caused choices are not free — and THAT premise is precisely what the compatibilist denies: the argument begs the question against compatibilism. The analysis is the model: name the parts, test the form, find the suppressed premise.

Personal identity 人格同一性 asks what makes you the same person over time, with three classic answers. The body theory 身体理论: numerical continuity of the organism (its strength: it matches how we identify people; its problem: the ship of Theseus — replace every part and identity seems untouched). The memory theory 记忆理论 (Locke): sameness of consciousness — memory connections join the person across time (its problem: Reid's brave officer — the old general remembers the officer, the officer the boy, the general not the boy: memory is not transitive, identity must be). The psychological continuity theory 心理连续性理论 (Parfit): overlapping chains of psychological connections; identity is not what matters, as the teleporter thought experiment suggests survival without identity, so personal identity may be a matter of degree.

Personhood 人格 asks what qualifies as a person — a moral category, not a biological one: humans are biological, persons are beings with rational agency, consciousness, the capacity for relationships (persons may be non-human; some humans, arguendo, may lack personhood). The criteria (self-consciousness, rationality, communication, moral agency) each draw edges — the infant, the severely cognitively impaired, the possible machine — which is why the concept is ethically loaded: abortion, end-of-life and animal ethics all turn on it. The craft applies: a criterion proposed, a counter-case found, the criterion refined.

The free will 自由意志 problem in one line: if every event has a cause, is any choice free? HARD DETERMINISM: no — causation is universal, freedom is an illusion, and moral responsibility needs rethinking. LIBERTARIANISM: yes — agents originate actions; at least some choices are uncaused causings (its burden: how an uncaused event can be controlled, and thus an agent's). COMPATIBILISM: freedom and determinism coexist — a free act is one caused in the right way, by the agent's own desires and reasons without coercion (its burden: if the desires are themselves caused, is the “right way” enough?). The thought experiments stress each: Frankfurt's unwilling addict (he acts on his desire but wants otherwise — unfree even undetermined? second-order desire as the key) and the manipulation case (a agent's desires implanted — desires “his own” by the compatibilist criterion, yet intuitively unfree).

The human condition frames the whole theme: that we are the animal that asks what it is — self-interpreting beings whose identities are partly chosen, partly given; finitude, embodiment and mortality as the conditions philosophy thinks within. And MIND: Dualism 二元论 (mind distinct from body — substance or property) against physicalism 物理主义 (all facts, mental included, are physical): the KNOWLEDGE ARGUMENT (Mary the scientist who knows all the physical facts and learns something new on seeing colour, a physicalist must say what she learns) and the ZOMBIE thought experiment (a being physically identical with no inner life — conceivable? and does conceivability entail possibility?).

• Argument anatomy: premises, conclusion, validity vs soundness, deduction vs induction; the named fallacies; the claim-reason-objection spine; thought experiments read as stress tests (craft).
• Identity: the three theories with their classic counter-cases (Theseus, Reid's officer, the teleporter); Parfit's survival-without-identity claim (identity).
• Personhood: the criteria and their edges; the moral uses of the concept (personhood).
• Freedom: hard determinism, libertarianism, compatibilism with each one's burden; Frankfurt's addict and the manipulation case (freedom).
• Mind: dualism vs physicalism; the knowledge argument and the zombie; what each shows and assumes (mind).
• The worked determinism argument's suppressed premise found and named (craft).

Boundary notes: the papers mark PHILOSOPHICAL SKILL — argument analysis in Section A, developed response in essays — and the core theme's concepts reappear in every optional theme. All worked examples are original; the classic cases cited are the standard canon.