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 and that "I" know what "thinking" is. He suggested a more appropriate phrase would be "it thinks" wherein the "it" could be an impersonal subject as in the sentence "It is raining." The Danish philosopher Søren Kierkegaard calls the phrase a tautology in his "Concluding Unscientific Postscript". He argues that the "cogito" already presupposes the existence of "I", and therefore concluding with existence is logically trivial. Kierkegaard's argument can be made clearer if one extracts the premise "I think" into the premises "'x' thinks" and "I am that 'x'", where "x" is used as a placeholder in order to disambiguate