People often say that a set of books looks ugly if all volumes are not in the same format, but I was impressed to hear the Abbot Koyu say, “It is typical of the unintelligent man to insist on assembling complete sets of everything. Imperfect sets are better.”
Yoshida Kenkō (1284–1350) Japanese author and Buddhist monk [吉田 兼好]
Essays in Idleness [Tsurezuregusa] (c. 1330)

