I used to keep my books pristine. Spines uncracked, pages unmarked, the whole shelf looking like a display in a shop window. It took me years to understand that I was protecting the object and losing the book.
Reading with a pencil changes the transaction. You stop receiving and start answering. A sentence arrives, you push back, and the pushing back is the part that is still with you a year later.
Start with three marks
You do not need a system. You need three marks you will actually use.
A vertical line in the margin means this matters. A question mark means I do not believe you. A small box around a word means look this up later, or steal this later, which are often the same thing.
That is the whole vocabulary. Everything else is decoration, and decoration is what makes people abandon annotation in the second week.
The point is not to remember the book. The point is to have argued with it.
Write the sentence you disagree with
The most useful marginalia is not the underline. It is the short, ungenerous note you scribble when an author overreaches. Six words in your own handwriting will outlast six pages of highlighting, because you had to think to produce them.
When you return to the book, those notes are a map of your own mind at that age. You get two texts for the price of one.
On lending marked books
People worry about this. Do not. A borrowed book full of your arguments is the most generous thing you can hand someone, and the only reason to hesitate is vanity.
Buy the paperback. Break the spine. Read with your hands.
