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mm.. perhaps I'm just not familiar enough with prolog, but I don't think it's possible to extract out a set of Prolog-level metavariables and compute over them? This is what's necesary to turn something like `_G947 -> _G947` into `forall a. a -> a`. but probably I just don't know enough. cool if you can, tho!

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That extraction is what the term_variables/2 predicate does that I use in my code. It gives you a list of all unbound variables in the given term. To simulate the quantification, I then just add that list in front of the term with the ^ operator (which has no semantics, it is just the traditional constructor for these things).

So for `_G947 -> _G947` I get the variable list `[_G947]` and use it to represent the universally quantified term as `[_G947]^(_G947 -> _G947)`. If you want to display this with nicer variable names, just substitute names of your choice for the variables in the quantifier list.

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