Kumayl bin Ziyad Nakha'i says that once Imam Ali put his hand in his hand and took me to the grave-yard. When he passed through it and left the city behind, he heaved a sigh and said 'Kumayl, these hearts are containers of the secrets of knowledge and wisdom and the best container is the one which can hold the most and what it holds, it can preserve and protect in the best way. Therefore, remember carefully what I am telling you. Remember that there are three kinds of people: one kind is of those learned people who are highly versed in the ethics of truth and philosophy of religion, second is the kind of those who are acquiring the above knowledge and the third is that class of people who are uneducated. They follow every pretender and accept every slogan, they have neither acquired any knowledge nor have they secured any support of firm and rational convictions. Remember, Kumayl, knowledge is better than wealth because it protects you while you have to guard wealth. It decreases if you keep on spending it but the more you make use of knowledge the more it increases. What you get through wealth dis- appears as soon as wealth disappears but what you achieve through knowledge will remain even after you.