 In reply, the existence monist could say that property instantiations metaphysically presuppose concrete objects as the instantiators of such  properties.[27]  That is, the existence monist should reply that existence nihilism is impossible, for positing properties without bearers. If so then at least one concrete object is required, by the argument that properties need bearers; and at most one concrete object is required, by the argument from exclusion discussed above.