Man is half an angel and half a devil, which was put forward by the ancient Greek philosopher Plotinus.
The original text is as follows:
We must be asked to regard human beings as the selected members of the universe and the most intelligent beings! But in fact, human beings are between beasts, sometimes biased towards one kind and sometimes biased towards another; Some people become more and more sacred, some people become wild animals, and most people maintain the golden mean. Man is half an angel and half a devil.
It means: "angel" is in people's hearts, and "devil" is also in people's hearts. Angels can breed ideals, honesty, love, integrity, honesty, selflessness and joy. Demons can produce evil, cruelty, ruthlessness, greed, jealousy and arrogance. Angels will become demons, and demons will become angels. Although this is not a law, it is undeniable.
Extended data
Plotinus's Central Philosophical Thought
Plotinus's metaphysics began with a holy trinity, namely "oneness", reason and soul. But these three are unequal, just like three of the Christian trinity;
Plotinus called it rationality. It is difficult for us to find an English word to express nous. The standard dictionary translation is "mind", but this does not mean its correct meaning, especially when the word is used in religious philosophy. If we say that Plotinus put his heart above his soul, we will create a completely wrong impression.
Mckenna, an English translator in Plotinus, used "reason-principle", but the word is still inappropriate. It does not mean that it is an object suitable for religious worship.
References:
Baidu Encyclopedia-Plotinus