I am wondering about the correct use of lesser/smaller in the following phrase:
This library has a smaller/lesser number of books than the National Library.
I did find another thread on nearly the same question, where one answer states: "As a general rule, 'smaller' is used for size, whereas 'lesser' is used for quantity." In this particular example, however, I am not quite sure how to approach this, as 'number' in this sentence refers to an amount, which you could argue has a size, and 'smaller/lesser number' as a whole only refers to a quantity.
To me, 'a smaller number' sounds better, but I am not a native speaker and I can't make out a clear reason for choosing one over the other.