• ttbc Dutch: onverbeterbaar (things), onverbeterlijk (living objects)
• ttbc German: unverbesserbar, unverbesserlich

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)http://www.thefreedictionary.com/Incorrigible 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 the nature of the proposition itself.

For illustration, consider Descartes': I think, therefore I exist. Stated in incorrigible form, this could be: "That I believe that I exist implies that my belief is true." Harrison argues that a belief being true is really only incidental to the matter, that really what the cogito proves is that belief implies existence. One could equally well say, "That I believe God exists implies that I exist," or "That I believe I do not exist implies that my belief is false."---and these would have the same essential meaning as the cogito.

Charles Raff draws a distinction between three types of incorrigibility:

• Type-1: It is logically necessary that, when the statement is sincerely made, it is true.
• Type-2: It is necessary that when the statement is believed to be true, it is true.
• Type-3: It is necessary that when the statement is true, it is believed to be true.

It should be noted that type-2 and type-3 incorrigibility are logical converses, and therefore logically independent. Charles Raff argues that introspection is not type-1 incorrigible, but is in fact type-2 and type-3 incorrigible.

References

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