Update forallx-ubc-5-SLtrees.tex

jonathanichikawa / for-all-x

Open-source logic textbook in LaTeX by UBC philosophy professor Jonathan Ichikawa

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Closed McTano closed 5 years ago

McTano commented 5 years ago

In the discussion on line 713 of checking the validity of an argument with a truth tree, the last sentence of the paragraph says.

If the tree closes, that suggests the argument is invalid. It should say the opposite, that a closed tree proves the argument is valid.

jonathanichikawa commented 5 years ago

Thanks!