oy as a man who exercises viceregal
functions, may have point as an epigram in the case of a _faineant_
viceroy, but it is not a definition.

So with the rule that "a definition should not be couched in ambiguous
unfamiliar, or figurative language". To call the camel "the ship of
the desert" is a suggestive and luminous description of a property,
but it is not a definition. So with the noble description of Faith as
"the substance of things hoped for, the evidence of things not seen".
But if one wonders why so obvious a "rule" should be laid down, the
answer is that it has its historical origin in the caprices of
two classes of offenders, mystical philosophers and pompous
lexicographers.[4]

That "the definition should be simply convertible with the term for
the class defined," so that we may say, for example, either: "Wine is
the juice of the grape," or, "The juice of the grape is wine," is an
obvious corollary from the nature of definition, but should hardly be
dignified with the name of a "rule".

_The Principles of_ NAMING. Rules have been formulated for the choice
of names in scientific definition and classification, but it may be
doubted whether such choice can be reduced to precise rule. It is
enough to draw attention to certain considerations obvious enough on
reflection.

We may take for granted that there should be distinct names for every
defining attribute (a _Terminology_) and for every group or class (a
_Nomenclature_). What about the selection of the names? Suppose an
investigator is struck with likenesses and differences that seem to
him important enough to be the basis of a new division, how should he
be guided in his choice of names for the new groups that he proposes?
Should he coin new names, or should he take old names and try to fit
them with new definitions?

The balance of advantages is probably in favour of Dr. Whewell's
dictum that "in framing scientific terms, the appropriation of old
words is preferable to the invention of new ones". Only care must be
taken to keep as close as possible to the current meaning of the
old word, and not to run counter to strong associations. This is
an obvious precept with a view to avoiding confusion. Suppose, for
example, that in dividing Governments you take the distribution of
political power as your basis of division and come to the conclusion
that the most important differences are whether this power is vested
in a few or in the majority of the comm