Basic principle and Hornbook

Basic principle noun - Principles from which other truths can be derived.

Hornbook and basic principle are semantically related. in something new topic. In some cases you can use "Hornbook" instead a noun phrase "Basic principle".

Hornbook noun - A primer that provides instruction in the rudiments or basic skills of a branch of knowledge.

Basic principle and hornbook are semantically related. Sometimes you can replace phrase "Basic principle" with "Hornbook", this terms are similar.