How to build Counter-Models from Proof Trees | First-Order Logic | Attic Philosophy

How do you build counter-models from first-order trees? You can build a model from any finished open branch on a proof tree. That model will satisfy the premises and the negated conclusion, so will be a counter-model to the inference you tested with the tree. In this video, I'll show you how to build the model.

00:00 - Intro
00:54 - Models from open branches
02:17 - Example without identity
04:31 - Building the model
05:32 - Interpreting Constants
06:31 - Interpreting predicates
09:41 - Example with identity
12:58 - More on the domain

If there’s a topic you’d like to see covered, leave me a comment below.

Links:

My academic philosophy page: http://markjago.net
My book What Truth Is: http://bit.ly/JagoTruth
Most of my publications are available freely here: https://philpapers.org/s/Mark%20Jago

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