Everything about Obversion
Immediate inference in logic
In traditional logic, obversion is a "type of immediate inference in which from a given proposition another proposition is inferred whose subject is the same as the original subject, whose predicate is the contradictory of the original predicate, and whose quality is affirmative if the original proposition's quality was negative and vice versa". The quality of the inferred categorical proposition is changed but the truth value is the same to the original proposition. The immediately inferred proposition is termed the "obverse" of the original proposition, and is a valid form of inference for all types of categorical propositions. Wikipedia →
🧭 Start here: a 6-step reading path
- Read the overview: ObversionA 5-minute orientation
- Pick up a classic book: The Power of LogicThe most-reprinted book on the subject
- Read the landmark paper: A NOTE ON OBVERSIONCited 2 times
- Go sideways: Categorical propositionA closely related topic
- Go sideways: ContrapositionA closely related topic
📖 Definitions
Noun The act of turning toward or downward.
Noun An immediate inference that denies the opposite of something previously affirmed.
🗂️ The subject at a glance
No outline available.
🏆 Landmark papers (most cited)
📚 Books worth reading
The Power of LogicFrances Howard-Snyder, Daniel Howard-Snyder · 2009- 📕ObverseChristine Ashby · 2020
Figures of literary discourseGérard Genette · 1982- 📕'Perle' and 'souillon'Susan Claire Yates · 1988
- 📕Zenith Lives! (Obverse Quarterly)Michael Moorcock
- 📕ObverseWill Daunt · 2022
- 📕Obversations 1Struan McAteer · 2001
The obversant voyageO. Brian Patrick · 2005
Ranked by number of editions on Open Library, a rough measure of how lasting a book is.
🔗 Related topics
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- The False Subtlety of the Four Syllogistic Figures The False Subtlety of the Four Syllogistic Figures Proved (German: Die falsche Spitzfindigkeit der vier syllogistischen Figuren erwiesen) is an essay published…
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