But I am a just man, even to my enemy—and I will acknowledge, beforehand, that they are cleverer brains than I thought them.

Man usually avoids attributing cleverness to somebody else unless it is an enemy.

Some years ago I read a book that brought Einstein's theory of relativity down to an eighth grade level. This convinced me that any subject can be made easy. In other words, always beware of anyone who tells you a topic is above you or better left to experts. This person may, for some reason, be trying to shut you out. You CAN understand almost anything.

Why do smart people exist, if not to figure out convoluted problems?

People should train their brain by watching films, by listening music, by playing games, by reading quotes. If people do this, I can said from this a big percent from here you can become clever.

Learn from acquaintances, and you are clever;
from friends, and you are intelligent; from enemies, and you are shrewd; but learn from all, and you are wise.