In philosophy, especially that of Aristotle, the golden mean is the desirable middle between two extremes, one of excess and the other of deficiency. For example courage, a virtue, if taken to excess would manifest as recklessness and if deficient as cowardice.
The Golden Section is a ratio based on a phi
The Golden Section is also known as the Golden Mean, Golden Ratio and Divine Proportion. It is a ratio or proportion defined by the number Phi (= 1.618033988749895… )
It can be derived with a number of geometric constructions, each of which divides a line segment at the unique point where:
the ratio of the whole line (A) to the large segment (B)
is the same as
the ratio of the large segment (B) to the small segment (C).
![Sectioning a line to form the Golden Section, based on phi, the golden ratio](http://www.goldennumber.net/wp-content/uploads/golden-proportion.gif)
In other words, A is to B as B is to C.
This occurs only where A is 1.618 … times B and B is 1.618 … times C.