抄録
Prof. Kobayashi criticized the Duhem-Quine thesis from an original point of view in his recent book Philosophy of Sience. His point is that there is "a difference of degree concerning theoreticity" which means the vulnerability to a theoretical revision in the whole system of physical theory. But, in my view, scientists cannot uniquely determine which is the object of revision between main hypotheses and auxiliary hypotheses. While in the "normal science" period auxiliary hypotheses are revised by falsificational experiments, only in the "scientific revolution" period main hypotheses are falsified. Therefore the so-called crucial experiment is no other than an honorary title which is awarded by historical consideration in a later period.