Didacticism

noun

1. The practice of conveying or of aiming to convey instruction; the tendency to be didactic in matter or style.
2. The didactic method or system.
3. An artistic philosophy that emphasises instructional and informative qualities over mere entertainment.
4. A work, statement, etc. of this kind.
5. communication that is suitable for or intended to be instructive

   "the didacticism of the 19th century gave birth to many great museums"