sophistry

n. fallacy, error in reasoning, misconception; deceptive argument

Sophism can mean two very different things: In the modern definition, a sophism is a confusing or illogical argument used for deceiving someone. In Ancient Greece, the sophists were a group of teachers of philosophy and rhetoric.The term sophism originates from Greek sophistes, meaning "wise-ist", one who "does" wisdom, one who makes a business out of wisdom (sophós means "wise man").
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(n.)
The practice of a sophist; fallacious reasoning; reasoning sound in appearance only.
  

(n.)
The art or process of reasoning; logic.
  

Noun
1. a deliberately invalid argument displaying ingenuity in reasoning in the hope of deceiving someone
(synonym) sophism, sophistication
(hypernym) fallacy, false belief