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I am building a weakened version of the intuitionistic logic. It wouldn't satisfy (p∧¬p)→⊥ as a tautology, but rather, (⊤→(p∧¬p))→⊥. In plain English, contradictions admit no proof, but there might still be true contradictions anyway. (Of course, here "true" doesn't mean "tautological")

By not fully accepting the law of noncontradiction, in addition to being intuitionistic, this logic system is paraconsistent. But how should I call ⊥, if a "contradiction" is meant to indicate p∧¬p?

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    What's wrong with "bottom"? Commented Feb 25, 2023 at 0:26
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    Your problem is not so much finding a name for ⊥ but giving its semantics. If your logic allows that some contradictions are true, then you cannot have the usual rules for bottom/falsum, or for negation for that matter. You might like to check out the answer to this question about minimal logic, which is also a paraconsistent sublogic of intuitionistic logic. math.stackexchange.com/questions/2625373/…
    – Bumble
    Commented Feb 25, 2023 at 6:33
  • There's merit to this question, intuitively, ja? 🙂
    – Hudjefa
    Commented Mar 15, 2023 at 13:09
  • The ⊥ sign, otherwise known as the uptack, is an unconditional false, or contridiction. Commented May 5, 2023 at 17:43
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    ⊥ in logic is often called "falsum". However, since ⊥ is also called a contradiction, it is unwise to declare that ⊥ isn't a contradiction, and also unwise to use the word "contradiction" to describe something that can be true in your system. Perhaps "P and not P" could be called a "conjunction of opposites", for example.
    – kaya3
    Commented Aug 17, 2023 at 11:08

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In a logic system that accepts true contradictions but not the law of noncontradiction, the symbol ⊥ (usually called "bottom" or "falsum") may represent something different than a standard contradiction (p∧¬p). You could refer to it as a "logical anomaly" or "logical inconsistency" to distinguish it from a standard contradiction.

So, in your system, you might say that (⊤→(p∧¬p))→⊥ represents the idea that contradictions do not necessarily lead to logical inconsistencies or anomalies. This approach aligns with the concept of paraconsistent logic, which allows for reasoning in the presence of contradictions without leading to triviality or inconsistency.

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