So much for some of the typical and instinctive cravings which cry
for satisfaction and are the causes of popularity. To them may be
added others of course, notably the desire for sudden wealth,
which is a factor in "Treasure Island" as in all treasure stories,
and the prime cause of success in the most popular of all plots,
the tale of Cinderella, which, after passing through feudal
societies with a prince's hand as reward, changed its sloven
sister for a shopgirl and King Cophetua into a millionaire, and
swept the American stage. To this may also be added simpler
stimulants of instinctive emotion, humor stirring to pleasant
laughter, pathos that exercises sympathy, the happy ending that
makes for joy. Stories which succeed because they stir and satisfy
in this fashion are like opera in a foreign tongue, which moves us
even when we do not fully understand the reason for our emotion.
They differ from another kind of popular story, in which a popular
idea rather than an instinctive emotion is crystallized, and which
now must be considered.

Each generation has its fixed ideas. A few are inherited intact by
the generation that follows, a few are passed on with slight
transformation, but most crumble or change into different versions
of the old half-truths. Among the most enduring of prejudices is
the fallacy of the good old times. Upon that formula nine-tenths
of the successful historical romances are built. That American
wives suffer from foreign husbands, that capital is ruthless, that
youth is right and age wrong, that energy wins over intellect,
that virtue is always rewarded, are American conceptions of some
endurance that have given short but lofty flights to thousands of
native stories.