Incorrigibility Incorrigibility In philosophy, incorrigibility is a property of a philosophical proposition, which implies that it is necessarily true simply by virtue of being believed. A common example of such a proposition is René Descartes' "cogito ergo sum" ("I think, therefore I am"). Johnathan Harrison has argued that "incorrigible" may be the wrong term, since it seems to imply (by the dictionary definition) a sense that the beliefs cannot be "changed", which isn't actually true. In Harrison's view, the incorrigibility of a proposition actually implies something about the nature of "believing"—for example, that one must exist in order to believe—rather than
Cogito, ergo sum for thought". In other words, "the only claim that is indubitable here is the agent-independent claim that there is cognitive activity present". The objection, as presented by Georg Lichtenberg, is that rather than supposing an entity that is thinking, Descartes should have said: "thinking is occurring." That is, whatever the force of the "cogito", Descartes draws too much from it; the existence of a thinking thing, the reference of the "I," is more than the "cogito" can justify. Friedrich Nietzsche criticized the phrase in that it presupposes that there is an "I", that there is such an activity as "thinking",