The Complete Aristotle (eng.)

river Maeander, and
of other peoples in Asia. Besides differences of wealth there are
differences of rank and merit, and there are some other elements
which were mentioned by us when in treating of aristocracy we
enumerated the essentials of a state. Of these elements, sometimes
all, sometimes the lesser and sometimes the greater number, have a
share in the government. It is evident then that there must be many
forms of government, differing in kind, since the parts of which
they are composed differ from each other in kind. For a
constitution is an organization of offices, which all the citizens
distribute among themselves, according to the power which different
classes possess, for example the rich or the poor, or according to
some principle of equality which includes both. There must
therefore be as many forms of government as there are modes of
arranging the offices, according to the superiorities and
differences of the parts of the state.
    There are generally thought to be two principal forms: as men
say of the winds that there are but two—north and south, and that
the rest of them are only variations of these, so of governments
there are said to be only two forms—democracy and oligarchy. For
aristocracy is considered to be a kind of oligarchy, as being the
rule of a few, and the so-called constitutional government to be
really a democracy, just as among the winds we make the west a
variation of the north, and the east of the south wind. Similarly
of musical modes there are said to be two kinds, the Dorian and the
Phrygian; the other arrangements of the scale are comprehended
under one or other of these two. About forms of government this is
a very favorite notion. But in either case the better and more
exact way is to distinguish, as I have done, the one or two which
are true forms, and to regard the others as perversions, whether of
the most perfectly attempered mode or of the best form of
government: we may compare the severer and more overpowering modes
to the oligarchical forms, and the more relaxed and gentler ones to
the democratic.
IV
    It must not be assumed, as some are fond of saying, that
democracy is simply that form of government in which the greater
number are sovereign, for in oligarchies, and indeed in every
government, the majority rules; nor again is oligarchy that form of
government in which a few are sovereign. Suppose the whole
population of a city to be 1300, and that of these 1000 are rich,
and do not allow the remaining 300 who are poor, but free, and in
an other respects their equals, a share of the government—no one
will say that this is a democracy. In like manner, if the poor were
few and the masters of the rich who outnumber them, no one would
ever call such a government, in which the rich majority have no
share of office, an oligarchy. Therefore we should rather say that
democracy is the form of government in which the free are rulers,
and oligarchy in which the rich; it is only an accident that the
free are the many and the rich are the few. Otherwise a government
in which the offices were given according to stature, as is said to
be the case in Ethiopia, or according to beauty, would be an
oligarchy; for the number of tall or good-looking men is small. And
yet oligarchy and democracy are not sufficiently distinguished
merely by these two characteristics of wealth and freedom. Both of
them contain many other elements, and therefore we must carry our
analysis further, and say that the government is not a democracy in
which the freemen, being few in number, rule over the many who are
not free, as at Apollonia, on the Ionian Gulf, and at Thera; (for
in each of these states the nobles, who were also the earliest
settlers, were held in chief honor, although they were but a few
out of many). Neither is it a democracy when the rich have the
government because they exceed in number; as was the case formerly
at Colophon, where the bulk of the inhabitants were possessed of
large property before the Lydian War. But the form of government is
a democracy when the free, who are also poor and the majority,
govern, and an oligarchy when the rich and the noble govern, they
being at the same time few in number.
    I have said that there are many forms of government, and have
explained to what causes the variety is due. Why there are more
than those already mentioned, and what they are, and whence they
arise, I will now proceed to consider, starting from the principle
already admitted, which is