Ronald W. Langacker created an approach to linguistics called Cognitive Grammar, which is essentially a system of symbols that can be used to organize and analyze how semantics and phonology interact with each other in human language. Cognitive Grammar lays the groundwork for cognitive linguistics, which has become a major sub-field over the past 30 years. Langacker's 2008 OUP book Cognitive Grammar is the authoritative introduction to CG. But for an introduction it's rather long-584 pages, divided into four sections, two of which are truly introductory and two of which offer a more...