13.04.2015 Views

Taylor - Theoretic Arithmetic.pdf - Platonic Philosophy

Taylor - Theoretic Arithmetic.pdf - Platonic Philosophy

Taylor - Theoretic Arithmetic.pdf - Platonic Philosophy

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

BOOK Two 103<br />

terms there is a greater ratio. But the harmonic middle is said<br />

to correspond to an aristocracy, because there is a greater ratio<br />

in its greater terms. And the geometric middle is analogous to<br />

a popular government, in which the poor as well as the rich<br />

have an equal share in the administration. For in this there is<br />

an equality of xatio both in the greater and the less termsox<br />

CHAPTER XXVI<br />

That plane numbers are conjoined by one medium only, but<br />

solid numbers by two media.<br />

IT is now time, however, that we should discuss certain<br />

things very useful to a knowledge of the fabrication of the<br />

world, as delivered in the Timaeus of Plato, but not obvious to<br />

every one. For all plane figures are united by one geometrical<br />

medium only; and hence in these there are only two intervals,<br />

viz. from the first to the middle, and from the middle to the<br />

third term. But cubes have two media according to a geornetrical<br />

ratio; whence also solid figures are said to have three in-<br />

+ With respect to these three middles, the arithmetic, the geometric and the harmonic,<br />

Proclus in Tim. p. 238. observes "that they pertain to the thre daughters<br />

of Themis, viz. Eunomia, Dice, and Irene. And the arithmetic middle indeed<br />

pertains to Irene or peace, which surpasses and is surpassed by an equal quantity,<br />

which middle we employ in our contracts during the time of peace, and through<br />

which likewise the elements are at rest. But the geometric middle pertains to<br />

Eunomia or equitable legislation, which also Plato denominates the judgment of<br />

Jupiter, and through which the world is adorned by geometrical analogies. And<br />

the harmonic middle pertains to Dice or Juctice, through which greater terms have<br />

a greater; but less, a less ratio."<br />

The geometric middle also comprehends the other two. For let there be any<br />

three terms in arithmetical proportion, for instance 1. 2. 3, and let a fowth term<br />

be added which shall cause all the four to be in geometrical proportion. This<br />

fourth term will be 6. For 1:2::3:6. This analogy therefore, wiIl comprehend<br />

both arithmetical and harmonica1 proportion. For 2. 3. and 6 arc in harmonic, and<br />

1. 2 and 3 in arithmetic proportion.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!