Through this exploration, he makes the case that gender has always existed
along a
spectrum: «We are all of us both male and female, and the way we express our «masculinity» and «femininity»
depends on the circumstances in which we find ourselves living.»
(Regarding PR, the fraction of PR from one layer that is absorbed by another
depends on their optical properties (as well as the optical properties of other layers in between, and other layers if scattering / reflection were to occur), including variations over the
spectrum and how the temperature change in the layer emitting the PR is distributed, which,
along with optical properties, affects how much PR goes out of a layer from the top or bottom, and where it is found in the
spectrum.