张五常先生的这五篇关于知识的短文写于十几年前，但是今天的人们读起来仍然津津有味，具有启发性，给人以知欲的满足。如果我们让身边那些被捧为理论家的人拿出十几年前写的东西来比较一下，就会发现那是另一种语境。人们为了不同目的而学术，往往发展后的现实能给予恰当的反 The five essays on knowledge by Mr. Zhang Wuchang were written a dozen years ago, but today people are still remembered, enlightening, and satisfied with their desires. If we compare those around us who are treated as theorists by comparing what we wrote a dozen or so years ago, we find that it is another context. People learn for different purposes, and the developed reality often gives the correct counter-measure