The undecidability of unification in third order logic
نویسندگان
چکیده
منابع مشابه
The Undecidability of Unification in Third Order Logic
The unification problem in a logic ~ is the following: given two well formed formulas e 1 and e 2 of ~-q~, decide whether there exists a substi tution a for the three variables of e 1 and e 2 such that a o e I and a o e~ are identical well formed formulas. The unification problem is decidable in first order logic. I t has been independent ly investigated by J. R. Guard (1964) under the name of ...
متن کاملOn the Undecidability of Second-Order Unification
There is a close relationship between word unification and secondorder unification. This similarity has been exploited, for instance, in order to prove decidability of monadic second-order unification and decidability of linear second-order unification when no second-order variable occurs more than twice. The attempt to prove the second result for (nonlinear) second-order unification failed and...
متن کاملThe Undecidability of Second Order Multiplicative Linear Logic
The multiplicative fragment of second order propositional linear logic is shown to be undecidable.
متن کاملThe Undecidability of Second Order Linear Logic Without Exponentials
Recently, Lincoln, Scedrov and Shankar showed that the multi-plicative fragment of second order intuitionistic linear logic is undecidable, using an encoding of second order intuitionistic logic. Their argument applies to the multiplicative-additive fragment, but it does not work in the classical case, because second order classical logic is decidable. Here we show that the multiplicative-addit...
متن کاملUndecidability of Compass Logic
It is known that the tiling technique can be used to give simple proofs of unde-cidability of various two-dimensional modal and temporal logics. However, up until now, the simplest two-dimensional temporal logic, the compass logic of Venema, has eluded such treatment. We present a new coding of an enumeration of the tiling plane which enables us to show that the compass logic is undecidable.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Information and Control
سال: 1973
ISSN: 0019-9958
DOI: 10.1016/s0019-9958(73)90301-x