The notion of ideas as infectious diseases is one to which most authoritarian religions and governments subscribe,

The notion of ideas as infectious diseases is one to which most
authoritarian religions and governments subscribe, and they hold
massive "hygienic" burnings of the "viral DNA" behind the ideas.
Promulgators of these "diseased" ideas are called "carriers of
spiritual impurity" (to use one phrase now popular in China) and
attempts are made to prevent the spread of these diseases. This is a
naive and dangerous view of how ideas work and it is disturbing to see
it rationalized into Western pop psychology.
-- Tim Maroney (tim@toad.com)