Democritus:

(460-370 BC) Greek pre-Socratic philosopher, from Thrace, primarily remembered for his formulation of an atomic theory of the universe; mentored by Leucippus, more a scientist than any other Greek philosopher; ignored in Athens, Plato disliked him intensely although Aristotle knew of his writing.  Only fragments of his work survive.

 

inter alia:

Latin, among other things

 

lodestar:

something that serves as a guide or on which the attention is fixed; a star that shows the way such as Polaris.