Subjectivism given consciousness is dependent on that consciousness. This has its philosophical basis in the writings of Descartes (see "cogito ergo sum"), and forms a cornerstone of Søren Kierkegaard's philosophy. Recently, more modest versions of metaphysical subjectivism have been explored. For example, I might hold that it is a "fact" that chocolate is tasty, even though I recognize that it is not tasty to everyone. This would imply that there are facts that are "subjective". (Analogously, one might hold that it is a fact that it is winter in the Northern Hemisphere, even though this is not always the case, implying
Cogito, ergo sum in the former case, and an objective thinker in the latter. He argues, first, that it is impossible to make sense of "there is thinking" without relativizing it to "something." However, this something cannot be Cartesian egos, because it is impossible to differentiate objectively between things just on the basis of the pure content of consciousness. The obvious problem is that, through introspection, or our experience of consciousness, we have no way of moving to conclude the existence of any third-personal fact, to conceive of which would require something above and beyond just the purely subjective contents of the mind.