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EsoLogic
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EsoLogic is an esoteric formal logic created because eso is fun.
Operators
EsoLogic has the standard operators from most formal logics, in a typable format. These include (which are primitive depends on who's defining):
φ&ψ: "φ and ψ"- logical conjunctionφ|ψ: "φ or ψ"- logical disjunction~φ: "not φ"- logical negationφ->ψ: "if φ then ψ"- implication
In addition, it borrows some things from other logics. For example, Temporal logic:
Xφ: "Next"- φ holds at the next stateGφ: "Global"- φ holds at all future statesFφ: "Final"- φ has to hold at some pointφUψ: "Until"- φ has to hold until ψ does, and can hold beyond.Hφ: "Historically"- φ has been true in the past
Fuzzy logic:
- Truth variables can have "degrees of truth" that are any real number such that 0≤n≤1
Epistemic logic:
Kτφ: "τ knows φ"- Agent τ knows that φ is trueBτφ: "τ believes φ"- Agent τ believes that φ is true
Communication epistemic logic:
Tτ,υΦ: "Tells"- τ tells υ that Φ (if υ trusts τ, then υ now knows/believes φ) (fails if~Kτφ)
Deontic logic:
Oτφ: "It is obligatory that τ φ"Pτφ: "It is permissible that τ φ"Fτφ: "It is forbidden that τ φ" (note that there's an operator collision here with Future)
And more stuff, when it is thought of.