The importance of this discussion, which went on in logical terms and is still going on all the time – there’s almost no day in which I do not have a fight against nominalism on the basis of my comparatively medieval realistic kind of thinking, which thinks that being is power-of-being. That is a sin against the “holy spirit” of nominalism, and therefore very much against the “unholy” spirit of logical positivism and many other such spirits. But I fight this fight because I believe that although extreme realism is wrong – namely that realism against which Aristotle was fighting in Plato, that the universals are special things somewhere in heaven – of course this has to be denied – – there are structures which actualize themselves again and again against all attempts of boys and stones and climate to make something else of them. They are always carried through. This is what I mean with “realism'”and so I can say, of being always resists non-being. And for this reason I believe that we cannot be nominalists alone, although the nominalist attitude, the attitude of humility towards reality, of not desiring to deduct reality, is something which we must maintain.