Maddalena Bonelli

«You cannot prove anything by crossing from another kind – e.g. something geometrical by arithmetic. There are three things involved in demonstration: one, what is being demonstrated, or the conclusion (this is what holds of some kind in itself); one, the axioms (axioms are the items from which the demonstrations proceed); third, the underlying kind whose attributes – i.e. the items incidental to it in itself – the demonstrations make plain» (Aristotle, Posterior Analytics 75a38-b2)...