type, object hierarchy?

[Terry Jones]

>>>>> "Arnaud" == Arnaud Delobelle <arnodel at googlemail.com> writes:

Arnaud> Are you suggesting a new axiom for propositional logic:
Arnaud> ((P => Q) ^ (R => Q)) => (P => R)  ?

Arnaud> I.e. in fruit logic: every orange is a fruit and every apple is a
Arnaud> fruit, therefore every orange is an apple.

This is otherwise known as Winterson's law:

  1. Every orange is a fruit
  2. Every apple is a fruit

  => Oranges are not the only fruit

Terry