So, this prompts me to ask, how many dictionaries and thesauri are too many? In general, how many reference books on any subject is too many to actually own - but language specifically? The range of words mostly overlaps and the definitions better be pretty darn consistent, right? There's value in getting a well-rounded, comprehensive definitions from more than one source, and full coverage of the breadth of the subject domain is essential, but at what point is there too much redundancy to warrant adding one more book?


As for heterogeneous shelves, do you see much value in adding dividers or spacers between groups? Labels maybe?