Graham Priest advocates the view that under some conditions, some statements can be both true and false simultaneously, or may be true and false at different times.

Graham Priest advances the strongest thesis of this sort, which he calls " dialetheism ".

* Graham Priest and Francesco Berto, " Dialetheism " ( Stanford Encyclopedia of Philosophy )

* Graham Priest and Koji Tanaka, " Paraconsistent logic " ( Stanford Encyclopedia of Philosophy )

Another reaction to the paradox of ( A ) is to posit, as Graham Priest has, that the statement is both true and false.

Graham Priest and other logicians, including J. C. Beall, and Bradley Armour-Garb have proposed that the liar sentence should be considered to be both true and false, a point of view known as dialetheism.

* Graham Priest ( 1984 ) " The Logic of Paradox Revisited ," Journal of Philosophical Logic 13: 153-179.

* Graham Priest, An Introduction to Non-Classical Logic: From If to Is, 2nd Edition, CUP, 2008, ISBN 978-0-521-67026-5

Some dialetheists, including Graham Priest, have argued that coherence may not require consistency.

Routley's work had particular influence for Graham Priest, a well-known proponent of non-classical logic ; Sylvan and Priest edited a well-regarded volume on the topic.

Graham Priest, of the University of Melbourne and the CUNY Graduate Center, is dialetheism's most prominent contemporary champion.

Graham Priest argues in Beyond the Limits of Thought that dialetheia arise at the borders of expressibility, in a number of philosophical contexts other than formal semantics.

Graham Priest once wrote " the whole point of the dialetheic solution to the semantic paradoxes is to get rid of the distinction between object language and meta-language ".

* Priest, Graham.

* Priest, Graham.

* Francesco Berto and Graham Priest.

For any two propositions and, the formula says that materially implies while says that strictly implies .< ref > Graham Priest, An Introduction to Non-Classical Logic: From if to is, 2 < sup > nd </ sup > ed, Cambridge University Press, 2008, ISBN 0-521-85433-4, p. 72.

* Priest, Graham, 2001.

* Graham Crowden as Old Priest

** Graham Priest ( born 1948 ), philosopher