Reddit mentions of Social and Cultural Anthropology: A Very Short Introduction

Sounds like you don't really understand how tribalism works, or why. Here's my favorite book on the subject but there are others: https://www.amazon.com/Social-Cultural-Anthropology-Short-Introduction/dp/0192853465

TL;DR people don't consciously choose to be tribal or to divide the world into tribes, and therefore it can be difficult for them to consciously choose not to be tribal, even if they want to.

Maybe think of it as fundamental knowledge? So, if you're attacking a new subject, identify the subcategories of the subject and the fundamental ideas behind each category. For example with music composition (which is my current endeavour) I'm identifying categories (or genres) of different music and learning the fundamentals behind each one. So currently I am going over my classical music knowledge (Haydn, Mozart and Beethoven studies), but I need to investigate the fundamental techniques behind other types of music, such as early music, jazz or contemporary styles. This gives me a sort of framework to work through, as I can identify what categories I need to know more about, and I can work chronologically through the history of music very easily.

In terms of identifying these categories, sometimes it can be obvious (there is a clear difference between jazz and classical) or they can be identified with just chronology by looking at a subjects development over time, but other times it would probably help to read an introductory book. I use the Very Short Introduction books, which have a massive range of topics, such as this one on Social & Cultural Anthropology or this one on Music I used. It lightly goes over a range of ideas in the subject, and you can pick out things you find interesting for further study.

Also I slightly disagree with Peterson about highlighting books, it can be good to highlight and bookmark small key quotes in a book, so you can later go back and reference a specific point word for word.

Hope that helps and is relevant.