Long before search engines, browser bookmarks or note-taking apps, careful readers kept a commonplace book: a personal volume into which they copied the passages, facts, arguments and observations they wanted to keep — organised so they could find them again, months or years later, and put them to use. Commonplace is that idea, rebuilt for the age of the web.
The practice runs from antiquity through the Renaissance and into the eighteenth and nineteenth centuries. Students were taught to keep one; scholars, lawyers, preachers, scientists and writers lived by theirs. It was not a diary and not a finished work — it was a working store of borrowed and original material, organised so the keeper could pull a passage back out and use it in an argument, a sermon, an essay, a decision.
The word itself comes from the Latin locus communis and the Greek koinos topos: a "common place" — a heading under which related material was gathered. That heading is the direct ancestor of the tag.
Paper and ink were cheap enough. The decisive problem was always retrieval. A book filled front-to-back in the order things were encountered becomes useless the moment it's full: you can't find anything. So the tradition developed techniques for organisation and indexing.
The most famous is John Locke's method, published in 1685 — a clever scheme for indexing a commonplace book by the first letter and first vowel of a keyword, so new entries could be added anywhere and still be found later. That tension — between the freedom to gather anything and the discipline needed to find it again — is the entire design problem Commonplace sets out to solve.
Locke's index, modernised. Where Locke had a first-letter, first-vowel rule, Commonplace has instant full-text search over every word you've saved — article text, a PDF's extracted words, a captured page, and your own notes — all in one index. The discipline the paper version demanded of its keeper is simply done for you.
Articles, PDFs, web pages, screenshots, half-formed notes, links we mean to read. The tools we use to gather it all pull in opposite directions — and none of them is a commonplace book.
The page changes or vanishes and the bookmark rots. Barely searchable, and nowhere to put a note about why you saved it.
Tuned for a list you drain, not a library you keep and revisit. And most are cloud services that own your material.
The OneNote / Obsidian / Notion family excel at prose, but treat a saved article as content dumped onto a page — not a structured record with provenance.
Zotero and kin model academic citation beautifully — but the ceremony is far too heavy for "I just want to keep this and find it later".
Each is good at part of the job. None is a commonplace book: a single, durable, searchable place where anything you find can live as a first-class record, with your own notes beside it, under headings that make sense to you. That's the gap Commonplace is built to fill.
Everything in the program traces back to one of these.
Not a blob of content — an object with a title, type, source, author, date, status, your notes, tags, and the full extracted text. That's what lets one search and one tag system span everything.
Fast full-text search is the heart of the program, not a feature bolted on the side. Locke's indexing problem, solved with a modern search index instead of the first-letter-first-vowel rule.
Local-first: the database and every saved file live in a readable folder on your own disk. Open it, back it up, move it, or walk away from the program entirely — you still have your files.
A commonplace book's value was often in the keeper's own marginal notes. So your notes sit beside every item and are folded into its searchable text — your thinking is as findable as the source.
A local-first commonplace book for the web — built on the oldest idea in personal knowledge work, with the retrieval power its paper ancestors never had.
Commonplace