Definition of petitio principii in English:
petitio principii
Pronunciation /pəˌtiSHēō prinˈsipēˌī/ /pəˌtɪʃioʊ prɪnˈsɪpiˌaɪ/
noun
Logic
A fallacy in which a conclusion is taken for granted in the premises; begging the question.
‘This, with great respect, is a petitio principii - reasoning which assumes the very thing which requires decision.’
- ‘Here I shall simply observe that the objection is a gross petitio principii.’
Origin
Latin, literally ‘laying claim to a principle’.