729/Historical Note

Historical Note on $729$
The philosopher rejected the well-known length of the year as being (approximately) $365 \frac 1 4$ in favour of $364 \frac 1 4$, as the latter is $729$, that is $9^3$, days and nights.

This was on the grounds that $9^3$ is:
 * the interval by which the tyrant is parted from the king.
 * -- 's Republic: $588$