Learn philosophy · Guide

How philosophy is organised here

Coordinates of Thought divides the same ground in two ways. The six roots and 131 question cards come from The Coordinates of Thought, the founder's book, which proposes one way of arranging philosophy's questions. The nine community categories are where members post, and they are cut for conversation. Traditions, schools, thinkers and concept tags run across both. Four posting formats, and the Journal for longer essays, tell readers what kind of contribution to expect. This page explains each one, how a newcomer can use it, and how the two schemes line up.

Updated 27 October 2026

The six roots and 131 cards are the scheme proposed in The Coordinates of Thought, the book this site grew from. No classification of philosophy is official: each one is a choice about emphasis.

Eight ways in

The Coordinates: 131 question cards
6 roots · 131 cards
Each root branches into question cards, 131 in all: 24 in Metaphysics, 18 in Epistemology, 21 in Ethics and Axiology, 16 in Logic, 11 in Aesthetics and 41 in the Philosophy of X. A card states one question in plain words, sets out the rival answers side by side and names who gave them, across traditions. Its address, such as 3.1.1, shows root, branch and sub-branch. Thirteen cards carry the contested mark (△), where philosophers dispute the framing of the question as well as the answer. A ◈ beside an answer marks a position that rejects the question's framing rather than answering it.
Open a card when you want the lie of the land before you argue. Read the rival answers, choose one under 'Where do you stand?' (or 'Not sure yet'), and follow the links to the cards it depends on or borders. When you want to argue for your answer, start a topic from the card.
Categories and their parts
9 categories · 67 parts
The community has nine categories: Metaphysics; Knowledge & Truth; Mind & Self; Ethics; Society & Politics; Religion & the Sacred; Logic, Language & Mathematics; Science & Technology; and Meaning, Art & the Good Life. Each is divided into parts, 67 in all, from Meta-ethics and Free will to Food & taste. The categories follow what people come to talk about, so Mind & Self and Religion & the Sacred stand on their own, although the roots place their questions in several branches. Each category has a subject guide.
Choose one category and one part for each topic you post, so that people who follow that subject see it. Before posting, read the category's subject guide and skim its recent topics: your question may already have a lively thread.
Traditions
16 traditions
A tradition is a lineage of thinkers who share languages, texts and a history of argument. The site uses sixteen: African & Africana, American, Analytic, Buddhist, Chinese, Continental, Greek & Roman, Indian, Indigenous, Islamic, Japanese & Korean, Jewish, Latin American, Medieval Christian, Modern European and Persian. A topic or a thinker can carry more than one.
Add a tradition when you are asking about that tradition's answer, or when your argument draws on its texts. A tradition's page gathers its thinkers and the conversations about them, which makes it a good way into unfamiliar thought.
Schools
76 schools
A school is a named movement or doctrine, narrower than a tradition: Stoicism, Madhyamaka, Nyāya, Mu'tazila, Neo-Confucianism, Pragmatism, Phenomenology and many more, 76 in all. Most belong to one tradition, as Nyāya belongs to the Indian and Ash'arism to the Islamic, but some, such as Feminist philosophy, run across several.
Add a school when your topic concerns a specific doctrine rather than a whole tradition. The guide to the schools of philosophy explains the main -isms and the questions each answers.
Thinkers
695 profiles
Every thinker has a profile with dates, places, key ideas and major works, from Thales and Confucius to living philosophers. Topics and Journal essays can be linked to the thinkers they discuss, and each profile collects those conversations. Profiles keep a permanent ID, so links survive a change of spelling.
Read a thinker's profile before reading their work, then follow the links to the cards where they appear. When you post about someone, tag them so your topic shows on their page.
Concept tags
3019 concept tags
Concept tags are short labels attached to topics, such as testimony or pramāṇa. They grow out of what members actually discuss, and they gather related topics across categories, traditions and formats.
Add one to three specific tags that a reader might search for. Prefer an existing tag to a new spelling of it, and use a tag to mark the second subject when a topic fits two categories.
The Book corner
725 books
The Book corner holds hundreds of books, from Plato and Aristotle to recent work, across eras and traditions, each with its own page. Members' own books are listed there too. A book page can start a reading group with the book already filled in.
Use the subject guides and the reading guides to choose a first book, then look it up in the Book corner. If you want company while reading, start or join a reading group from the book's page.
Formats
4 formats
What kind of conversation a topic is: a question, a debate, a discussion or a reading group.
Use them to find the kind of conversation you want.
Questions
A question asks for explanation or gathers different answers. It suits a clear, focused puzzle: what a term means, how two views differ, or what others think about a case.
Put the question itself in the title, say what you already know or think, and link the card it touches. Mark replies as helpful when they help.
Debates
A debate starts from one clear claim, the thesis, such as 'The self is not the body'. Others argue for or against it.
State your thesis as a single sentence you are prepared to defend, give your best argument, and name the strongest objection you know. Argue with the claim, never with the person.
Discussions and thoughts
A discussion opens a longer conversation on any idea, without a fixed thesis. A thought is a lighter discussion: one line is enough, such as a passage that struck you or a half-formed objection.
Share a thought when something catches your attention and you want to see where others take it. Start a discussion when you have more to say, but are still thinking it through rather than defending a position.
Reading groups
A reading group reads one text together, section by section, at an agreed pace. It suits classics that are hard to read alone, from the Analects to the Critique of Pure Reason.
Propose a reading group with the text, the edition or translation and the first section to read. Post a short summary and one question for each section, and keep to the schedule so latecomers can catch up.
Journal essays
The Journal publishes longer essays, of at least 300 words, by members and by the editors, on philosophy from every tradition. An essay is written from Your page, stays a draft until you send it to the editors, and is published after review. Essays carry the same labels as topics.
Write an essay when you have worked an argument through and want it read as a whole. Choose a category, traditions, thinkers and tags as you would for a topic, so readers can find it.

The six roots

The roots follow the questions themselves: what exists, what can be known, what is good, what follows from what, what beauty is, and those questions aimed at one part of life.

MetaphysicsWhat exists, and what is it like?24 cards
EpistemologyWhat can be known, and how?18 cards
Ethics and AxiologyWhat is good, and what should I do?21 cards
LogicWhat follows validly from what?16 cards
AestheticsWhat is beauty, and why does art move us?11 cards
The Philosophy of XThe questions above, aimed at one part of life.41 cards

The nine categories and their parts

The categories follow conversations: where people bring a question, and where others will look for it. Each category page is also a guide to its subject.

Crosswalk: which roots each category draws on

Each number counts the question cards filed under that category’s parts, and so the cards its conversations link to. Read across a row to see which roots a category draws on; read down a column to see where a root’s questions are discussed.

Categories (rows) and the six roots (columns): question cards in each
Subject	I Metaphysics	II Epistemology	III Ethics and Axiology	IV Logic	V Aesthetics	VI The Philosophy of X
Metaphysics	14 cards	none	none	none	none	none
Knowledge & Truth	none	16 cards	none	none	none	none
Mind & Self	5 cards	1 card	none	none	none	4 cards
Ethics	none	none	20 cards	none	none	none
Society & Politics	none	none	none	none	none	15 cards
Religion & the Sacred	1 card	1 card	none	none	none	2 cards
Logic, Language & Mathematics	1 card	none	none	16 cards	none	4 cards
Science & Technology	3 cards	none	none	none	none	9 cards
Meaning, Art & the Good Life	none	none	1 card	none	11 cards	7 cards

A number: cards filed there. The editors relate the category to that root, though no card is filed under it yet. None.

Metaphysics. All 14 cards discussed under its six parts come from Root I. Existence & being takes Ontology, Substance, Universals, Mereology and Meta-Metaphysics; the other parts take the cards on time, space, causation, modality, free will, laws and emergence. Root I's other ten cards are discussed elsewhere: mind in Mind & Self, cosmology in Science & Technology, natural theology in Religion & the Sacred, and Abstract Objects (1.1.4) in Logic, Language & Mathematics.
Knowledge & Truth. Its seven parts (Knowledge & belief, Reason & experience, Evidence & testimony, Skepticism, Truth, Rationality & probability, Disagreement & expertise) take 16 of Root II's 18 cards. The other two, Perception (2.2.1) and Revelation (2.2.5), are discussed in Mind & Self and Religion & the Sacred.
Mind & Self. Consciousness and Personal identity take the five Philosophy of Mind cards from Root I (1.3 to 1.3.4). Emotions, Action & agency, Artificial minds and Psychology & the mind sciences take four Root VI cards (6.23, 6.24, 6.17, 6.14). Perception takes 2.2.1 from Root II.
Ethics. Its nine parts, from Meta-ethics and Moral theories to Bioethics and War & violence, take 20 of Root III's 21 cards. The twenty-first, Value Theory (3.5), is discussed under Happiness & well-being in Meaning, Art & the Good Life.
Society & Politics. All 15 of its cards come from Root VI, spread across its ten parts from Justice to Society & culture. They cover law, education, political philosophy and its three sub-cards, economics, history, social ontology, social science, work, disability, gender, race and culture.
Religion & the Sacred. Faith & reason and Mysticism & spirituality take Philosophy of Religion and Religious Experience (6.1, 6.1.1) from Root VI. God & the arguments takes Natural Theology (1.8) from Root I, and Revelation & scripture takes Revelation (2.2.5) from Root II. Religions compared and The problem of evil have no card of their own yet.
Logic, Language & Mathematics. All 16 Logic cards (Root IV) sit in Logic & argument, Fallacies & paradoxes, Rhetoric & persuasion and Modal & non-classical logic. Meaning & language takes the three Philosophy of Language cards (6.10 to 6.10.2) and Philosophy of mathematics takes 6.9, both from Root VI, plus Abstract Objects (1.1.4) from Root I.
Science & Technology. Scientific method takes the four Philosophy of Science cards (6.8 to 6.8.3). Physics & cosmology takes 6.11 and Root I's three cosmology cards (1.2 to 1.2.2). Biology & evolution, Medicine & health, Technology & the future and Information take 6.12, 6.13, 6.16 and 6.18. AI & computing has no card of its own; the AI card (6.17) sits in Mind & Self.
Meaning, Art & the Good Life. Beauty & art and Music & literature take all 11 Aesthetics cards (Root V). Love & friendship, Death, Meaning of life, Play, sport & humour, Food & taste and Film & media take seven Root VI cards (6.19 to 6.21, 6.25 to 6.27 and 6.32). Happiness & well-being takes Value Theory (3.5) from Root III.

Traditions and schools

Traditions and schools cut across both schemes: a Buddhist argument about the self belongs to the root of metaphysics, the category Mind & Self, and the Buddhist tradition all at once.

Traditions

Schools

Questions people ask

Is this the official way to divide philosophy?

No. There is no official division, and every scheme is a choice about emphasis. The six roots and 131 cards are the founder's proposal in The Coordinates of Thought. The Stoics divided philosophy into logic, physics and ethics, and the Nyāya Sūtra begins its sixteen topics with the means of knowledge. Use the roots as a working tool, and argue with them where you think they cut in the wrong place.

Why are there six roots but nine categories?

They do different jobs. The roots classify questions by what they ask; the categories gather conversations by what people come to talk about. Philosophy of mind, for example, is a group of cards within Metaphysics, but people discuss it so much that Mind & Self is a category of its own. The crosswalk on this page shows which roots each category draws on.

My question fits two categories. Where should it go?

Post it in the category where you most want replies, and choose the part that fits best. Then mark the second subject with a concept tag, or link the card that connects them, so readers from the other side can find it.

What is the difference between a tradition and a school?

A tradition is broad: a lineage of thinkers sharing languages, texts and a history of argument, such as Chinese or Islamic philosophy. A school is a named doctrine or movement, usually within one tradition, such as Mohism within Chinese philosophy or Mu'tazila within Islamic thought. A topic can carry both.

What does the △ mark on a card mean?

It marks one of the 13 contested cards, where philosophers disagree about how the question should be framed, or whether it is a separate question at all, as well as about the answer. The card sets out every side and takes none.

Should I ask a question, start a debate or open a discussion?

Ask a question when you want explanations or a range of answers. Start a debate when you have one claim you are ready to defend. Open a discussion, or share a one-line thought, when you are still thinking aloud. A reading group is for working through one text together.

Where does a long piece of writing go?

In the Journal. Essays of 300 words or more are written from Your page and sent to the editors, who review them before publishing. Shorter pieces work better as a discussion or a thought.

Will my first posts appear straight away?

Your first topics are read by an editor, usually within a day. Once three have been published and you have been a member for a month, your topics appear straight away.

Every question here has serious answers on more than one side. Join free to ask, reply and take sides; reading is free for everyone.