TEHRAN, Young Journalists Club (YJC) -
Imam Ali (pbuh), the Commander of the Faithful:
The most wonderful thing in human is his heart which includes a constellation of wisdom and anti-wisdom. If it is dominated by desire, then avarice debases it; if avarice enters it, then greed ruins it; in if its is overcome by disappointment, then sadness kills it,... . So every dereliction of it is harmful for it and every excessiveness about it leads to its corruption.
Source: Illal ul-Shrayi, vol. 1, p. 109