This is a historical question about philosophical views. I believe I understand the claim made by Wittgenstein and others that logical propositions are tautologies. I'd like to know what other views there are, and if other philosophers don't agree that logical propositions are tautologies, how do they characterize logical propositions?

Here's the section from the Tractatus:

6.1 The propositions of logic are tautologies.

6.11 The propositions of logic therefore say nothing. (They are the analytical propositions.)

In addition, this answer says that:

The claim that propositions of logic, and analytic truths in general, are tautologies was a consensus view before Frege, and can be found in Locke, Hume and Kant

What other views are/were there on the issue? I'm interested in views held by philosophers now, as well as throughout history.

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    Wittgenstein is the inventor of the technical term "tautology" and the main source of the truth table method. But in the Tractatus he stated the view that all logical truth are tautologies, which is not : x=x is a valid formula of first order logic (and thus a logical truth) but it is not a tautology of propositional logic. Apr 5, 2019 at 18:59
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    The pre-Wittgenstein sense of tautology was "devoided of content": this was the view of Kant (but not of Frege). Apr 5, 2019 at 19:00
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    According to Mill, they are highly general, and elementary, empirical generalizations, according to Frege, they are "laws of thought", and according to late Wittgenstein they are "grammar" of reasoning, a practically followed convention mapped into words.
    – Conifold
    Apr 5, 2019 at 21:25


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