Physiognomy is the study of one's inner being (thoughts, feelings, etc) in it's relation with one's outer being, or action (speech, facial expressions, handwriting, tone of voice, etc).
Physiognomy was dubbed a pseudoscience by G.F.W. Hegel in his Phenomenology of Spirit alongside phrenology, or the (equally pseudoscientific) "science" of skull measurement, which Hegel denounced. Phrenology was the basis of the race theories of National Socialism.
Infrared often jokes that Hegel should have given more thought to the concept and that Trofim Lysenko's agronomic work vindicated the theory of physiognomy; IGG also jokes that their enemies are ugly inside and this typically makes them ugly on the outside as well, such as Drew Pavlou or Destiny.