The Collaborative International Dictionary of English v.0.48:

Encyclopedism \En*cy`clo*pe"dism\, n.
   The art of writing or compiling encyclopedias; also,
   possession of the whole range of knowledge; encyclopedic
   learning.
   [1913 Webster]

WordNet (r) 3.0 (2006):

encyclopedism
    n 1: profound scholarly knowledge [syn: eruditeness,
         erudition, learnedness, learning, scholarship,
         encyclopedism, encyclopaedism]