思

silent contemplation

extremism; radical belief

mutual affection; mutual love

the philosophy of the European Enlightenment

freethinker

free thought

to worry; to fret; to be anxious

Seven Wonders of the World

Buddhism

Buddhist thought; Buddhist concept

Idiomatic expression

not give a damn; not care a bit

meditation

worrying about one's master's affairs; one who so worries

one's own volition

pessimism due to decadent-age theory

eugenic thought; idea of eugenics

scientific thought

thought of the times

central idea

old-fashioned idea

Mao Zedong thought; Maoist thought; Maoism

feudalistic thought or thinking

rumination; ruminating; careful pondering

economic ideology; (school of) economic thought

lateral thinking