21

G21

supervenes upon a surprise is either a recollection of some
circumstance which, if we had thought of it in the first instance, would
have prevented the surprise (a case hardly worth notice from the
point of view of logic,) or else is a conjecture that the surprising
phenomenon is somehow connected with some other fact within our cognizance.

How many such facts are there? The most skillful
player of the game of twenty questions, in which one person thinks of
some quite noticeable object, while concerning which the other party asks questions that
can be answered by 'yes' or 'no,' usually has to exhaust his twenty