Editing Sum of Logic (section)

==Book III.  On Syllogisms==

===Part I.  On Syllogisms===

{{ordered list
|list-style-type=lower-roman
|On categorical syllogisms (1&ndash;19)
|On modal syllogisms (20&ndash;30)
|On mixed syllogisms (31&ndash;64)
|On syllogisms containing exponible propositions
}}

===Part II.  On Demonstration===

* These 41 chapters are a systematic exposition of Aristotle's [[Posterior Analytics]].

===Part III.  On Consequences===

* The first 37 chapters of Part II are a systematic exposition of Aristotle's [[Topics (Aristotle)|Topics]].  In Part III, Ockham deals with the definition and division of consequences, and provides a treatment of Aristotle's Topical rules.<ref>Boehner p.54</ref>  According to Ockham a consequence is a [[conditional sentence|conditional proposition]], composed of two categorical propositions by the terms 'if' and 'then'. For example, 'if a man runs, then God exists' (''Si homo currit, Deus est'').<ref>Boehner pp. 54–5</ref>  A consequence is 'true' when the [[antecedent (logic)|antecedent]] implies the [[consequent]]. Ockham distinguishes between 'material' and 'formal' consequences, which are roughly equivalent to the modern [[Material conditional|material implication]] and [[Logical consequence|logical implication]] respectively.  Similar accounts are given by [[Jean Buridan]] and [[Albert of Saxony (philosopher)|Albert of Saxony]].
* Chapters 38 to 45 deal with the [[Theory of obligationes]].
*Chapter 46 deals with the [[Liar paradox|Liar Paradox]]

===Part VI.  On Fallacies (in 18 chapters)===
Part IV, in eighteen chapters, deals with the different species of fallacy enumerated by Aristotle in [[Sophistical Refutations]] (''De sophisticis elenchis'').

*Chapters 2-4 deal with the three modes of [[equivocation]].
*Chapters 5-7 deal with the three types of [[Amphibology|amphiboly]].
*Chapter 8 deals with the fallacies of [[Fallacy of composition|composition]], and [[Fallacy of division|division]].
*Chapter 9 deals with the [[fallacy of accent]].
*Chapter 10 deals with the fallacy of 'figure of speech'.
*Chapter 11 deals with the [[Accident (fallacy)|fallacy of accident]].
*Chapter 12 deals with the fallacy of [[affirming the consequent]].
*Chapter 13 deals with ''[[secundum quid|secundum quid et simpliciter]]''.
*Chapter 14 deals with [[Ignoratio elenchi]] or irrelevant thesis.
*Chapter 15 deals with [[begging the question]] (''petitio principii'').
*Chapter 16 deals with [[Questionable cause|false cause]] (''non-causam ut causam'')
*Chapter 17 deals with the [[Complex question|fallacy of many questions]] (''plures interrogationes ut unam facere'')>
*Ockham ends (chapter 18) by showing how all these fallacies err against the syllogism.