Paragraph 1 | Similarly they can all be formed in the last figure. |

Paragraph 2 | But to prove that A belongs to some B, this hypothesis must be made. |

Paragraph 3 | When A belongs to no B, suppose A belongs to some B, and let it have been assumed that C belongs to all B. |

Paragraph 4 | But this hypothesis must be made if we are prove that A belongs not to all B. |

Paragraph 5 | It is clear then that in all the syllogisms which proceed per impossibile the contradictory must be assumed. |

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