Knowing things halfway is a greater success than knowing things completely: it takes things to be simpler than they really are andso makes its opinions more easily understandable and persuasive.
Whereas young people become accomplished in geometry and mathematics, and wise within these limits, prudent young people do not seem to be found. The reason is that prudence is concerned with particulars as well as universals, and particulars become known from experience, but a young person lacks experience, since some length of time is needed to produce it.
True science investigates and brings to human perception such truths and such knowledge as the people of a given time and society consider most important. Art transmits these truths from the region of perception to the region of emotion.
The thief steals from himself. The swindler swindles himself. For the real price is knowledge and virtue, whereof wealth and credit are signs. These signs, like paper money, may be counterfeited or stolen, but that which they represent, namely, knowledge and virtue, cannot be counterfeited or stolen.
For knowing is spoken of in three ways: it may be either universal knowledge or knowledge proper to the matter in hand or actualising such knowledge; consequently three kinds of error also are possible.
From whatever you wish to know and measure you must take your leave, at least for a time. Only when you have left the town can yousee how high its towers rise above the houses.