Look at Mencius with your heart: "Those who devote themselves to it know their nature, and those who know their nature know heaven."
Do, expand;
Heart refers to the so-called natural compassion, shame, resignation and right and wrong.
Intellectuality refers to understanding the so-called nature endowed by talent, that is, benevolence, righteousness, courtesy and wisdom.
Mencius believed that if people can expand and give play to their "original heart", they can know their own nature-four ends, because "original heart" contains their own nature, and once they are "intellectual", they can know the "destiny" and "know the sky with one heart".