Recommending The Jazz Theory Book to someone starting from scratch, especially someone self studying, is like recommending CLRS or TAOCP to someone who asks "I'm curious about learning the basics of algorithms and data structures, any good books for self study?" And of course that happens all the time too. Chapter 1 is "here's what intervals like major 3rd and perfect fifths are", Chapter 2 is "here's the major scale and all its diatonic modes and ii-V-I progressions", Chapter 3 is "here's how you might use the Phyrigian mode to play over a Sus flat-9 chord" (pg 48).
Recommending Schoenberg and Messiaen as steps to get a sufficient surface of topics covered for "music theory" is performance art in its own regard. Bravo!