The classic typographic scale is a collection of font sizes chosen for their visual appeal—as in a musical scale, where every note is proportional and in harmony with the others. A musical composition only uses notes that appear in the chromatic musical scale, and a typographical composition only uses font sizes that appear in the classic typographic scale.
The classic typographic scale is a scale, so it must obey the scaling property: if f is a size in the scale, then rf must also be a size in the scale, where r is the ratio of the scale.
