"There are three things--and these are important--that produce prudence together with wisdom: namely nature, experience, and learning. The former two are common to nearly all people, nevertheless their nature is such that unless the third factor, i.e., learning and discipline, is joined with them, the one (nature) cannot be developed and the other (experience) cannot be employed in practical matters. For God has given us the power of mind together with life; some experience must exist in the man who has been given a rather long life and endowed with some diligence. But either one becomes worth more if a teacher of letters is brought in. When God has given to the teacher a good nature, he stands out always as useful and often as wholesome for the citizenry. But when literary elegance has been improperly applied to corrupted minds, frequently evil and very often wicked examples are apt to result.
For there is nothing more potent than learning. It has the greatest potential both for harming and for helping man. Many wise men have been nonchalant and contemptuous with impunity before threats of kings and tyrants who could not bear the enmity of poets or the shouting of orators. Therefore the arts and disciplines should be taught not only in conformance with the rules of the arts, but also in a way that promotes wholesomeness--both of which in our times have been vitiated."
Johann Sturm on Education, Spitz and Tinsley (pg 73)