Sentence:  In contrast to this Stoic patristic view , Utopia implies that the nature of man is such that to rely on individual <WSD>conscience</WSD> to supply the deficiencies of municipal law is to embark on the bottomless sea of human sinfulness in a sieve . 
Meaning of the word marked with <WSD> tags:  motivation deriving logically from ethical or moral principles that govern a person's thoughts and actions