Is n't the ocean such a big thing?
The earth is such a big thing. I have read that Sun is 100 times larger than the Earth. I could comprehend it.
The universe is such a big thing. No one can tell whether it is finite or infinite. It is, at least, beyond my comprehension.
I am a teacher with a doctorate degree. I can not comprehend my own mind. The more I know about it, I will come to know that there is more about it.
“Wisdom begins with wonder,” said Socrates. Through dialogue, he led his audience to passionate inquiry of existence and identity. In his mind, one could not know anything without knowing one’s self. Thus, the Seven Sages of Greece, who had inscribed "know thyself" in the forecourt of the Delphic oracle a few generations before Socrates, had challenged all subsequent philosophers to attain self-knowledge before knowing anything else.
In 1750 Benjamin Franklin, in his Poor Richard's Almanack, observed the great difficulty of knowing one's self, with: "There are three Things extremely hard, Steel, a Diamond, and to know one's self."