Ian Darwin has been a bibliophile since his teenage years; he wanted to open a physical bookstore before Amazon came along. Books here are from his personal bookshelf, and he hopes somebody new will cherish them all - if you buy one you don't like, please either let me know, or, pass it on to somebody who will.
The ISBN was first introduced in 1970, that is, 54 years ago as of 2024. Thus, any book that pre-dates the use of ISBNs can be considered antiquarian. That is the criteria used to divide books into the two main categories.