I thought the reason for a textbook was for it to be linear. Otherwise, people could just use the encyclopedia.
The preliminary OChem book I am playing with has trains of continuity, although they are more flexible than in a printed book. Its a flexibility to link to all related subjects that I wish the textbooks that I use had. I dont think that most people would confuse an interlinked textbook with an encyclopedia, as a textbook seeks to actively teach, where an encyclopedia presents information more passively. Plus there is an overlying scheme of nested links that adds structure. But thats just how I see this book on this subject turning out right now, and is no comment on any other book or any other way or etc.
I guess a textbook as I see it should help lead a person thru the subject even if it gives him freedom to change direction. Isnt learning more fun for you as a learner when you have some say on how you do it ?
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