Wisdom is the right use of knowledge. To know is not to be wise. Many men know a great deal, and are all the greater fools for it. There is no fool so great a fool as a knowing fool. But to know how to use knowledge is to have wisdom.
How would it be possible if salvation were ready to our hand, and could without great labor be found, that it should be by almost all men neglected? But all things excellent are as difficult as they are rare.