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Old question

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Shouldn't it read "x (mod 2) \equiv 0"?

Is this article encyclopedic?

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I've never heard of this term, and the article does not provide any references to this usage. It looks bogus to me. Any defenders? --- Charles Stewart 17:52, 19 May 2005 (UTC)[reply]

Merge

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I think this should be merged with judgment. 'Assertion' is introduced as a synonym for judgment in (Martin-Löf 1983) 'On the Meanings of the Logical Constants and the Justification of Logical Laws', and indeed the present content of this page expresses a special case of what can be found at judgment. Quiddital (talk) 22:26, 13 August 2016 (UTC)[reply]

No. This is wrong. A judgment is a type judgment, as in type theory. Judgments are used to define logics, so you cannot make a logical assertion until a logic is defined, first. See natural deduction for examples of how to define a logic, and how to use judgments to create that definition. 67.198.37.16 (talk) 21:52, 18 December 2018 (UTC)[reply]

Wrong wrong wrong and wrong!

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This article is very misguided.

  • It is not hypotheses that are asserted.
  • It is provable formule that are asserted not truths (the set of things provable and the set of things true may not coincide).
  • Assertions in programming languages such as C are quite different from assertions in the logical sense. 86.132.216.101 (talk) 17:45, 19 September 2016 (UTC)[reply]

How should this be understood?

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The current article contains this text:

For example, if p = "x is even", the implication

which is clear-as-mud and/or wrong. I suspect the parenthesis is mis-placed. I suspect it should be

If I try to read the former, with the bad paren placement, I start with which can be readily recognized as a tautology: from nothing at all, from thin air, I can prove that p is true. Since its a tautology, p is always true. So this reduces to , which is blatently wrong, unless x is restricted to be a member of the set of even natural numbers. For example, x must not belong to the set of quadruped furry animals, because is not even well-defined for furry animals.

The second form with re-arranged parenthesis, makes slightly more sense, but is still ill-defined. There, the reading starts with , so that p is now some proposition, might be true, might be false, who knows, but whenever p is true, then if follows that . Presumably, it works out that whenever p is true, then x is even.

Oh, hang on. It also says: ''For example, if p = "x is even",... and so perhaps this is meant to be the definition of what p is? In that case, simple substitution works. That is, perform the substitution aka . The first formula gives

which is insane because is not a tautology. The second form gives

which obviously is a tautology, and totally acceptable. 67.198.37.16 (talk) 15:48, 18 December 2018 (UTC)[reply]