measuring two feet; but he is to have no previous knowledge of the
matter, and is not to be directly coached by Socrates. He is to
discover the answer for himself. Actually the slave first gives out
an incorrect answer. He answers that the length of a rectangle
having twice the area of the one mentioned is four feet, thinking
that the length doubles with the area. Thereupon Socrates triumphantly
points out to Meno that the slave does as a matter of
fact not yet quite know the truth under consideration, but that he
really thinks he knows it; and then Socrates, in his own Socratic
way, leads the slave to the correct solution. This very significant
procedure of the philosopher is cited by Guggenheim[1] as an
illustration of the essence of a priori knowledge, and when we properly
consider what we have to do with a witness who has to relate
any fact, we may see in the Socratic method the simplest example
of our task. We must never forget _that the majority of mankind
dealing with any subject whatever always believe that they know and
repeat the truth_, and even when they say doubtfully: ``I believe.--
It seems to me,'' there is, in this tentativeness, more meant than
meets the ear. When anybody says: ``I believe that--'' it merely
means that he intends to insure himself against the event of being
contradicted by better informed persons; but he certainly has not

[1] M. Guggenheim: Die Lehre vom aprioristischen Wissen. Berlin 1885.

the doubt his expression indicates. When, however, the report of
some bare fact is in question (``It rained,'' ``It was 9 o'clock,''
``His beard was brown,'' or ``It was 8 o'clock,'') it does not matter
to the narrator, and if he imparts _*such_ facts with the introduction,
``I believe,'' then he was really uncertain. The matter becomes