Books the intellectuals used to use, containing good arguments and ideas for reference.
Commonplace books were physical books created by intellectuals of the past. They would keep them to face a COMMON PLACE To keep passage of text for reference, well formed arguments, and ideas they were incubating. These people would:
Read in Fits and starts and jump from book to book. They broke texts into fragments and assembled them into new patterns by transcribing them in different sections of their notebooks. Then they reread copies and rearranged the patterns while adding more excerpts. Reading and writing were therefore in separable activities.
These Evergreen Notes you’re reading right now are the modern iteration of commonplace Books.