Too wide a question, but I will say that everyone's thinking is shaped not only by individual native biology but also by individual culture and experiences. A book I recently listened to took a good stab at explaining form a variety of disciplines. I include some editorial reviews so you can get a better idea of the book.

Behave: The Biology of Humans at Our Best and Worst

"Sapolsky has created an immensely readable, often hilarious romp through the multiple worlds of psychology, primatology, sociology and neurobiology to explain why we behave the way we do. It is hands-down one of the best books I’ve read in years. I loved it."— Dina Temple-Raston, The Washington Post

Rarely does an almost 800-page book keep my attention from start to finish, but
If anyone can save evolutionary biology from TED talkers and pop-science fabulists, it might be Sapolsky…. Behave ranges at great length from moral philosophy to social science, genetics to Sapolsky’s home turf of neurons and hormones—but all of it is aimed squarely at the question of why humans are so awful to each other, and whether the condition is terminal.” —Vulture

“This is a miraculous book, by far the best treatment of violence, aggression, and competition ever. It ranges from how neurons and hormones interact, how emotions are an essential part of decision making, why adolescents are more likely to be violent than adults, why genes influence cultures and vice-versa, and the ins and outs of “we versus them,” all the way to “live and let live” truces in World War I and the My Lai massacre. Its depth and breadth of scholarship are amazing, building on Sapolsky’s own research and his vast knowledge of the neurobiology, genetic, and behavioral literature. For instance, Behave includes fair evaluations of complex debates (like over sociobiology) that I was involved in, and tackles controversial questions such as whether our hunter-gatherer ancestors warred on each other. He even takes on “free will” with a clarity usually absent from the writings of philosophers on the subject. All this is done brilliantly with a light and funny touch that shows why Sapolsky is recognized as one of the greatest teachers in science today.” —Paul R. Ehrlich, author of Human Natures

Yo PL, but of course, that is impossible to answer. Because! When you reach the end of your ability to divine, what is beyond that barrier is unknown. Therefore, you do not know if you have just 1% of reality in your grasp, or if u may have as much as 99% of reality in u'r grasp. If I had to guess, I would guess, some nominal percentage.

As far as possible

As far as necessary to find a split or some sort of understanding.....

My thinking on everything is everything I can imagine.

This is much too vague a question to answer....”everything” ? You will have to have a rethink about how you wish to phrase the question. Everything, is much too all encompassing a word, narrow it down to something less nebulous.