The Corner Marking Method
- Difficulty
- Starter
- Time to result
- ~days to results
- Steps
- 6
- Confidence
- —
Newport's deliberately low-friction alternative to Zettelkasten-style note capture for non-fiction research. Reading with a pencil, when a page contains something he might need for a book or article, he draws a line across the upper corner so the page is findable by flipping, then brackets the relevant sentences. That is the entire method — no cards, no filing, no post-reading processing session. The trade is explicit: you lose a little information, but you can pick up a 500-page book years later, flip through in four minutes finding every corner-marked page, read the bracketed sentences, and in about five minutes reload what mattered in it. Newport's justification is that he goes through a lot of books, and any overhead heavy enough to make him hesitate before reading is a worse cost than the information loss.
Origin
Extracted from Deep Dive with Ali Abdaal
How to run it
- 1
Read physical non-fiction with a pencil
Apply the method to non-fiction sources you think you will need for a book or article. The tool is a pencil, deliberately — nothing to boot up, nothing to sync.
- 2
Mark the corner when a page is relevant
Draw a line across the upper corner of any page containing something that seems relevant. This creates a hash mark visible from the page edge, which is what makes retrieval fast.
Pro tip Corner marks are findable by flipping, which is why they beat underlining alone.
- 3
Bracket the relevant sentences
On that page, bracket out the specific sentences you think matter. Mark the corner, bracket the lines — and that is it.
- 4
Do no processing afterwards
Skip the step where you transfer, summarise or file the ideas. Newport specifically rejects the Zettelkasten habit of spending significant time processing thoughts from books after reading them.
Watch out Adding a processing ritual is what makes the whole system heavy enough that you read fewer books.
- 5
Reload the book on demand
When you need the source, flip through finding every corner mark — four minutes even for a 500-page book — and read the bracketed sentences. In roughly five minutes the useful content is back in your head.
Pro tip This works on books read many years earlier.
- 6
Accept the lossiness as the price
Acknowledge you lose a little information versus a full note system, and treat that as the deliberate purchase price for near-zero friction across a large volume of reading.
In the wild
Newport wanted something from Douglas Rushkoff's Present Shock, a book he had read around 2009. Rather than searching notes or rereading, he picked up his marked copy, flipped through for the corner hash marks, and read the bracketed sentences. In about five minutes the whole book was swapped back in — not every detail, but the material that had struck him as relevant at the time. He describes doing the same thing the same day with a 500-page book, finding every marked page in roughly four minutes.
→ A decade-old source became usable for current writing in five minutes with no note-processing debt ever paid.
Common mistakes
Adopting a heavy capture system
Card-based methods require a processing pass after each book; for someone who reads at volume, that overhead quietly reduces how much you read at all.
Marking everything
The corner mark only makes retrieval fast if marked pages are rare. Bracket what you think you will actually need, not everything interesting.
From the transcript
“Well, so so yeah, I do uh I call the corner marking method.”
“So, mark the corner, bracket out the things you think are relevant.”
From the episode
Cal Newport: Lifestyle Design, Slow Productivity and Contrarian Writing
Cal Newport