Dichotomy
Part of speech: noun
Definition: A cutting in two; a division. Division or distribution of genera into two species; division into two subordinate parts. The phase of the moon in which it appears bisected, or shows only half its disk, as at the quadratures. Successive division and subdivision, as of a stem of a plant or a vein of the body, into two parts as it proceeds from its origin; successive bifurcation. The place where a stem or vein is forked. Division into two; especially, the division of a class into two subclasses opposed to each other by contradiction, as the division of the term man into white and not white. conditions perceived as polar extremes or opposites an either-or perspective
Example sentence: Obama is trying to paint us as a caricature, as if we're some bizarre individualists who are hardcore libertarians. It's a false dichotomy and intellectually lazy. Of course we believe in government. We think government should do what it does really well, but that it has limits.
Duality
Part of speech: noun
Definition: A classification into two subclasses or opposed parts.The interchangeability of points and planes.The mathematical equivalence of two seemingly different theoretical descriptions of a physical system.
Example sentence: The idea of 'Freedom's Goblin,' to me, leads to a wild conversation. I would hope that father and son, driving home from the record store, could have a conversation about what that title means. Because to me, it's the duality of being free: the evil and the good, and how it's a constant paradox.