e sun's course in different parts of the
earth. The fixed stars have also two movements--a forward movement in
their orbit which is common to the whole circle; and a movement on the
same spot around an axis, which Plato calls the movement of thought
about the same. In this latter respect they are more perfect than the
wandering stars, as Plato himself terms them in the Timaeus, although in
the Laws he condemns the appellation as blasphemous.

The revolution of the world around earth, which is accomplished in
a single day and night, is described as being the most perfect or
intelligent. Yet Plato also speaks of an 'annus magnus' or cyclical
year, in which periods wonderful for their complexity are found to
coincide in a perfect number, i.e. a number which equals the sum of its
factors, as 6 = 1 + 2 + 3. This, although not literally contradictory,
is in spirit irreconcilable with the perfect revolution of twenty-four
hours. The same remark may be applied to the complexity of the
appearances and occultations of the stars, which, if the outer heaven is
supposed to be moving around the centre once in twenty-four hours, must
be confined to the effects produced by the seven planets. Plato seems to
confuse the actual observation of the heavens with his desire to find in
them mathematical perfection. The same spirit is carried yet further
by him in the passage already quoted from the Laws, in which he affirms
their wanderings to be an appearance only, which a little knowledge of
mathematics would enable men to correct.

We have now to consider the much discussed question of the rotation or
immobility of the earth. Plato's doctrine on this subject is contained
in the following words:--'The earth, which is our nurse, compacted (OR
revolving) around the pole which is extended through the universe, he
made to be the guardian and artificer of night and day, first and eldest
of gods that are in the interior of heaven'. There is an unfortunate
doubt in this passage (1) about the meaning of the word (Greek), which
is translated either 'compacted' or 'revolving,' and is equally capable
of both explanations. A doubt (2) may also be raised as to whether the
words 'artificer of day and night' are consistent with the mere passive
causation of them, produced by the immobility of the earth in the midst
of the circling universe. We must admit, further, (3) that Aristotle
attributed to Plato the doctrine of the rotation of the earth on its
axis