can make meaningful statements about bodies without referring to substances. Argument from conception Another argument for the substance theory is the argument from conception. The argument claims that in order to conceive of an object's properties, like the redness of an apple, one must conceive of the object that has those properties. According to the argument, one cannot conceive of redness, or any other property, distinct from the substance that has that property. Criticism The idea of substance was famously critiqued by David Hume, who held that since substance cannot be perceived, it should not be assumed to exist. Friedrich Nietzsche, and after him Martin Heidegger, Michel Foucault and Gilles Deleuze also rejected the notion of "substance", and in the same movement the concept of subject - seeing both concepts as holdovers from Platonic idealism. For this reason, Althusser's "anti-humanism" and Foucault's statements were criticized, by Jürgen Habermas and others, for misunderstanding that this led to a fatalist conception of social determinism. For Habermas, only a subjective form of liberty could be conceived, to the contrary of Deleuze who talks about "a life", as an impersonal and immanent form of liberty. For Heidegger, Descartes means by "substance" that by which "we can understand nothing else than an entity which is in such a way that it need no other entity in order to be." Therefore, only God is a substance as Ens perfectissimus (most perfect being). Heidegger showed the inextricable relationship between the concept of substance and of subject, which explains why, instead of talking about "man" or "humankind", he speaks about the Dasein, which is not a simple subject, nor a substance. Alfred North Whitehead has argued that the concept of substance has only a limited applicability in everyday life and that metaphysics should rely upon the concept of process. Roman Catholic theologian Karl Rahner, as part of his critique of transubstantiation, rejected substance theory and instead proposed the doctrine of transfinalization, which he felt was more attuned to modern philosophy. However, this doctrine was rejected by Pope Paul VI in his encyclical Mysterium fidei. Bundle theory In direct opposition to substance theory is bundle theory, whose most basic premise is that all concrete particulars are merely constructions or 'bundles' of attributes or qualitative properties: Necessarily, for any concrete entity, , if for any entity, , is a constituent of , then is an attribute. The bundle theorist's principal