originate in instinctive desires, or in preferences acquired
through habit. Common sense finds fixed pigeon holes
into which to fit all the variety of specific circumstances and
conditions which characterize experience. "When its judgments
happen to be correct, it is almost as much a matter of
good luck as of method.... That potatoes should be planted
only during the crescent moon, that near the sea people are
born at high tide and die at low tide, that a comet is an
omen of danger, that bad luck follows the cracking of a
mirror," all these are the results of common-sense observation.
Matters of common knowledge are thus not infrequently
matters of common misinformation.

Common-sense knowledge is largely a matter of uncritical
belief. When there is absent scientific examination of the
sources and grounds of belief, those judgments and conclusions
are likely to be accepted which happen to have wide
social currency and authority. In an earlier chapter, it was
shown how the mere fact of an opinion prevailing among a
large number of one's group or class gives it great emotional
weight. Where opinions are not determined by intelligent
examination and decision, they are determined by force of
habit, early education, and the social influences to which one
is constantly exposed.

The scientific spirit is a spirit of emancipated inquiry as
contrasted with blind acceptance of belief upon authority.
The phenomenal developments of modern science began
when men ceased to accept authoritatively their beliefs about
man and nature, and undertook to examine phenomena in
their own terms. The phenomenal rise of modern science is
coincident with the collapse of unquestioning faith as the
leading ingredient of intellectual life.

Common sense renders men peculiarly insensitive to the
possibilities of the novel, peculiarly susceptible to the
influence of tradition. It was common sense that credited the
influence of the position of the stars upon men's welfare, the
power of old women as witches, and the unhealthiness of night
air. It was common sense also that ridiculed Fulton's steamboat,
laughed at the early attempts of telegraphy and telephony,
and dismissed the aeroplane as an interesting toy. The
characteristic feature of common sense or empirical thinking
is its excess traditionalism, its wholesale acceptance of authority,[1]
its reliance upon precedent. Where beliefs are not subjected
to critical revision and examination, to t