Natural Deduction Systems in Logic




Philosophy News image

[New Entry by Francis Jeffry Pelletier and Allen Hazen on October 29, 2021.]
‘Natural deduction’ designates a type of logical system described initially in Gentzen (1934) and Jaśkowski (1934). It also designates the type of reasoning that these logical systems embody. A fundamental part of natural deduction, and what (according to most writers on the topic) sets it apart from other proof methods, is the notion of a “subproof”. Although formalisms differ, an underlying idea is that one is able to “make an assumption A and see that it leads to conclusion X”, and then conclude that…

Continue reading . . .

News source: Stanford Encyclopedia of Philosophy



Whispering Monuments

Whispering Monuments

n this beautifully illustrated talk, China historian Robert Bickers explores the lost monuments of Shanghai. Leading us through the complex...

The Roof-Watcher

After the Agamemnon of Aeschylus Late afternoon of that unending year’s first day, I cringed at clangs, at god strikes...

The Kyoto School

[Revised entry by Bret W. Davis on November 28, 2023. Changes to: Main text, Bibliography, notes.html] The Kyoto School (Kyōto-gakuha)...