Boolean negation and non-conservativity III: the Ackermann constant
Tore Fjetland Øgaard · Logic Journal of IGPL · 2020
Abstract It is known that many relevant logics can be conservatively extended by the truth constant known as the Ackermann constant. It is also known that many relevant logics can be conservatively extended by Boolean negation. This essay, however, shows that a range of relevant logics with the Ackermann constant cannot be conservatively extended by a Boolean negation.