Winning the Numbers Game
Mathematics is a unique subject. It grows and advances like other fields but rarely is any "old" mathematics deemed incorrect or even out of date. Sciences like biology and physics are different. Today's theories generally replace yesterday's. Social sciences like psychology and sociology are subject to the same dynamics. In fields where sciences and social sciences are applied (e.g., to computers or education), changes in knowledge can happen even faster.
How do these observations about the nature of knowledge in various fields apply to book buying and selling? Like this: If I am at a sale and I see a 30-year-old mathematics text, I will seriously consider buying it. If I see a 5-year-old book on computer operating systems, I will skip it without looking back.
In this article I will take you through the realm of mathematics books and give you an idea of what is potentially valuable and what to avoid. You do not have to know the mathematics contained inside the books to succeed at buying and selling these profitably. However, as in all fields, subject knowledge does give the bookseller an edge. I simply hope that after reading this article you will be more likely to look at mathematics books than you were before and not be inclined skip over them at sales, if that was your habit.
Mathematics books that one might find while book scouting fall roughly into five categories, some of which may overlap:
Introductory Undergraduate Books
Currently, introductory courses in college mathematics include (along with remedial courses): Arithmetic, Algebra, Elementary Algebra, Intermediate Algebra, College Algebra, Liberal Arts Mathematics, Statistics, Finite Mathematics, Discrete Mathematics, Pre-Calculus, and Calculus. Many titles in this category review (or elaborate on) high school material, so things may look familiar to you when you page through the books.
With the exception of some calculus students, most users in this category are enrolled in non-math, non-engineering, or non-science majors. Consequently, when the semester ends, most of these books are usually sold, given away, donated or otherwise disposed of. Typically, they are also large and heavy. In the effort to appeal to the largest number of mathematics departments, publishers cram them with everything imaginable. Once every three to four years the publisher will issue a new edition. Some teachers won't immediately use the new edition, so the previous edition may retain some resale value, but rarely will anyone use a book more than one edition old. (There are notable exceptions - for example, Finite Mathematics by Maki and Thompson (4th Edition, 1996) which has been in use for years at many universities.)
Recent textbooks can be quite lucrative for the bookseller. By "recent" I mean publication dates between 2003 and 2006. When I am at a big book sale and time is of the essence, I usually reject any introductory mathematics texts that are more than three years old. Currently, this means I would reject 2002 or older editions if I didn't have time to ScoutPal them.