A commonplace book is a notebook where you copy out things worth keeping — passages from what you read, lines from conversations, facts, definitions, arguments you want to remember. Not your own thoughts, primarily. Other people’s.
The practice is old. Locke wrote a method for it, Marcus Aurelius’s Meditations is arguably one, and it was standard equipment for educated readers for several centuries before the index card and then the app displaced it.
It is worth reviving for one specific reason: a commonplace book is the only reading system where the act of keeping it does the work. Copying a passage by hand is what makes you own it.
Commonplace book versus the alternatives
| Contents | Organized by | Read again? | |
|---|---|---|---|
| Commonplace book | Other people’s words, copied out | Chronological, with an index | Constantly — that is the point |
| Journal or diary | Your own life and thoughts | By date | Occasionally |
| Reading journal | Books you read, with responses | By book | By title |
| Notes app | Everything, searchably | Search | Almost never, honestly |
The notes-app row is the one worth sitting with. Digital highlighting is frictionless, which is exactly its problem: nothing is selected, nothing is retyped, and nobody ever opens the export file.
How to start, in about ten minutes
- Take a notebook you already own. Anything with numbered or numberable pages. Do not buy a special one; the beautiful blank notebook is why people never start.
- Number the pages, bottom outer corner. Ten minutes for a hundred pages, and this single step is what makes the index possible.
- Leave the first four pages blank. This is the index. It fills in over years.
- Start writing on page five. Copy one thing you read this week.
- Write the source underneath. Author, title, page. Always. A quote without a source is worth much less in five years, and you will not remember.
That is the whole setup. Everything else is refinement.
The index
The index is the difference between a commonplace book and a pile of nice sentences. It is a subject index, not a table of contents.
On your index pages, keep a running list of topics with page numbers after them:
| Topic | Pages |
|---|---|
| Attention | 7, 19, 44, 61, 88 |
| Courage | 12, 40 |
| Grief | 23, 31, 55, 90 |
| Habit | 9, 15, 15, 72 |
| Money | 28, 66 |
| Time | 5, 33, 47, 47, 81, 95 |
The rule: when you write an entry, immediately add its page number to one or two topics in the index. One or two, not five — over-indexing makes every topic useless.
Alphabetize loosely. Give each letter a block of lines on the index pages rather than trying to keep a perfect alphabetical list. Locke’s original method was more elaborate; a rough letter-block is enough for a notebook.
Invent topics as you need them. Do not design the taxonomy first. After a year your index will tell you what you actually care about, which is one of the quieter pleasures of the whole practice.
A worked entry
What a page actually looks like:
|
p. 44 "[The passage, copied by hand, however long it needs to be.]" — Author name, Title, p. 212 Why I kept this: one line, in your own words. Not analysis — just what made you stop. → index: attention, work |
The "why I kept this" line is optional and it is the one most people add after six months, once they have gone back to an entry and had no idea why past-them cared.
What goes in it
Anything you would be sorry to lose. In practice:
- Passages from books, obviously — but only the ones you would copy out by hand, which is a much shorter list than the ones you would highlight.
- Lines from poems, songs, films, sermons.
- Things people actually said to you. These age better than anything else in the book.
- Definitions and words you had to look up.
- Facts you keep forgetting.
- Arguments you want to be able to reconstruct.
- Recipes, if you like — there is a long tradition of this.
- Lists: rules for something, the questions worth asking, what someone said made a good life.
What does not go in: your own daily thoughts. That is a journal, it is a good thing to keep, and mixing the two produces a book you cannot use for either purpose.
The rules that make it last
Copy by hand. Not typed, not photographed, not clipped. The friction is the feature — it is what makes you choose, and choosing is the whole practice.
Do not organize by theme as you write. Chronological, in the order things arrived. The index does the finding. Trying to keep themed sections means running out of room in one and wasting pages in another.
Do not skip the source. Every time. It takes four seconds.
Keep it to one book. Fill it, then start volume two with a fresh index. Multiple books running at once defeats the index.
Reread it. Twenty minutes, a few times a year, just flipping. This is where the value actually appears — passages you kept for one reason turn out to be about something else entirely once you have lived a bit longer.
Common mistakes
Copying too much. If you are transcribing three pages of a book, you did not select anything. A commonplace book is an argument about what matters, made by omission.
Buying a beautiful notebook first. It becomes too nice to write in badly, and every commonplace book has bad handwriting in it.
Skipping the page numbers. Then there is no index, and then it is a pile of nice sentences.
Trying to make it digital. You can, and people do. But the searchable version removes the friction that made the practice worth doing, and what you get is a database nobody reads.
Start with one passage
Take a notebook, number twenty pages, leave the first four blank, and copy out one thing from whatever you are reading now. Add its page number to one topic in the index.
That is a commonplace book. In two years it will be the most valuable notebook you own, and it will have cost about ninety seconds a week.
A 5x7 discbound notebook works well for this because you can add pages to the index section as it fills, which a bound book cannot do. If you are marking passages as you read, the annotation color key is the companion habit — the quote symbol in the margin becomes your to-copy list — and a reading journal is the per-book record that sits alongside it.