A: The delay you experience is because I used Brython (a Python interpreter written in Javascript) to develop the page. If you know some web development, Right-click > View source code on any of the site's excercise pages and you will se what i'm talking about.

A: Please write to me at [email protected]. If you can include a screenshot, I will be very thankful.

A: Then you might want to check out Reconstructor. Reconstructor's base language allows you to define a first-order language with indefinitely many constants, predicates, variables and even function symbols. It also contains arithmetic, set theory and other mathematics inside the object language.

A: For classical logic (and intuitionist and minimal natural deduction systems), you may see L.T.F. Gamut (1991) Logic, language and meaning (there is a spanish translation available). For the non-classical multivalued logics of the FDE family, see Priest (2008) An Introduction to Non-Classical Logic in english, Da Ré & Roffé (2016) Introducción a las Lógicas Modales y No-clásicas in spanish. For the logics with consistency (or inconsistency) operators inside the object language (such as LFI1), see Carnielli & Coniglio (2016) Paraconsistent Logic.

Programming & Project direction: Ariel Roffé
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