Ideas
The concepts that move through history and change shape.
Dharma
The central idea of Indian civilisation — the order that holds the world together, and the duty, law, virtue and right way of living that each being owes to it. For Buddhists, the Dhamma is also the Buddha’s teaching and the ultimate constituents of reality.
Ātman is Brahman
The central Upanishadic insight — the innermost Self of each being is identical with the ultimate reality of the universe.
Karma
“Action” — and the law that every intentional action leaves a trace that ripens, in this life or a future one, as happiness or suffering. Shared by Hindus, Buddhists, Jains and Sikhs, karma explains the inequalities of fortune without a judge, and binds the self to the round of rebirth.
Mokṣa
Liberation — release from the cycle of rebirth and from all suffering, the highest goal of human life in the Hindu and Jain traditions (and, as nirvāṇa, in Buddhism). Every Indian school defines it differently, and the arguments over what it is, and how it is won, are the backbone of Indian philosophy.
Saṃsāra
“Wandering” — the beginningless cycle of birth, death and rebirth through which beings pass according to their karma, and from which every major Indian religion seeks release.
Anattā (No-Self)
The Buddha’s teaching that there is no permanent, unchanging self — only a flowing stream of physical and mental processes.
Anekāntavāda
The Jain doctrine that reality is many-sided — that every thing has infinite aspects and every statement captures only one, so that truth requires holding many viewpoints together. Expressed in the parable of the blind men and the elephant and formalised in the sevenfold logic of syādvāda.
Nothing from Nothing
The ancient principle that nothing comes from nothing — the foundation of Greek physics and the target of the Christian doctrine of creation from nothing.
Nirvāṇa
The Buddhist goal — the “blowing out” of the fires of greed, hatred and delusion, the end of suffering and of rebirth. The Buddha described it as unborn and unconditioned, and refused to say whether the awakened exist after death.
Pratītyasamutpāda (Dependent Origination)
The Buddha’s central insight — “when this exists, that comes to be; when this ceases, that ceases.” Nothing exists independently; everything arises from conditions. Applied to suffering, it becomes the twelve-linked chain from ignorance to death.
The Forms
Plato’s eternal, perfect, unchanging realities — Beauty itself, Justice itself, the Good — of which the things we see are imperfect copies.
Eudaimonia
Flourishing, living well — Aristotle’s name for the highest human good, activity of the soul in accordance with virtue.
Śūnyatā (Emptiness)
Emptiness — the Mahāyāna teaching that all things lack intrinsic, independent existence (svabhāva), because they arise in dependence on causes, parts and concepts. Not nothingness, but the openness that makes change and freedom possible.
Rasa
The Indian theory of aesthetic experience — the “flavour” or “relish” that art evokes in the audience. Bharata named eight rasas; Abhinavagupta added peace and explained rasa as the self tasting its own consciousness through universalised emotion.
Māyā
The power of appearance — in Advaita, the cosmic illusion by which the one Brahman appears as a world of many things.
Cogito, ergo sum
I think, therefore I am — the one certainty Descartes found after doubting everything else.
The Problem of Induction
No non-circular argument shows that the future will resemble the past — yet all science and daily life depend on it.
Hume's Fork
Every meaningful claim is either a relation of ideas (certain but empty) or a matter of fact (informative but uncertain) — metaphysics is neither.
Synthetic a priori
Judgments that are informative about the world yet knowable independently of experience. Kant’s master question was how they are possible.
The Thing-in-Itself
Reality as it is independently of how it appears to us — for Kant, thinkable but never knowable.
The Categorical Imperative
Kant’s supreme principle of morality — act only on maxims you could will as universal laws; treat humanity always as an end, never merely as a means.
The Copernican Revolution
Kant’s reversal — instead of the mind conforming to objects, objects must conform to the mind’s forms of knowing.
Dialectic
The movement of thought — and for Hegel, of reality — through contradiction toward a richer unity.
Geist (Spirit)
Hegel’s name for reality as self-knowing mind unfolding through nature, history, culture and philosophy.
The Will
Schopenhauer’s name for the thing-in-itself — a blind, aimless, insatiable striving that expresses itself in everything, from gravity to human desire.
The Leap of Faith
Kierkegaard’s claim that faith cannot be reached by reasoning — it is a passionate decision made in the face of the absurd.
Anxiety
Not fear of something, but dread before freedom and nothingness — for Kierkegaard “the dizziness of freedom”, for Heidegger the mood that reveals the nothing.
Rational Egoism
Chernyshevsky’s doctrine that people always act from self-interest, and that enlightened self-interest will make everyone good.
Eternal Recurrence
Nietzsche’s thought-experiment — would you will to live your life again, every moment, infinitely? The supreme test of affirming life.
The Death of God
Nietzsche’s announcement that belief in God has become unbelievable — and that with Him the foundations of Western morality have gone.
The Übermensch
Nietzsche’s “overman” — the human being who, after the death of God, creates new values and affirms life wholly.
Will to Power
Nietzsche’s idea that the basic drive of all life is not survival but growth, mastery, self-overcoming.
Master and Slave Morality
Nietzsche’s genealogy — “good/bad” was the self-affirmation of nobles; “good/evil” was invented by the resentful weak to revenge themselves on the strong.
Dasein
Heidegger’s term for the human being — “being-there” — the entity whose own being is an issue for it.
Bad Faith
Self-deception about one’s own freedom — pretending to be a thing, determined by role or nature, to escape the anguish of choice.
Existence Precedes Essence
Sartre’s formula — humans have no pre-given nature; we exist first and make ourselves through our choices.