I am not sure that this question should be posted to you, philosophers. But I think philosophy has been talking about everything in life. Anyway, my question is : Do we have to has a fix principles and values that never be changed? I mean, we almost consider changing is a positive thing, and everything we believe in must be criticized and examined and consequently, changed ... if so, is it reasonable for people to Struggle for their principles If they believe that this principle may be changed anytime? Does the fact of “change” eliminates the value of”principle”? Thank you

Thank you for this inquiry! You raise a complex matter. Some philosophers have gone through changes, sometimes quite radical: we sometimes refer to the pre-critical Kant and then to Kant after the Critique of Pure Reason, Wittgenstein changed his mind in such a significant way that we refer to the early and the later Wittgenstein, same with Heidegger. I am not sure that we can say (in the abstract) that change is itself a good or value: there is a famous philosopher of mind, Frank Jackson, who first introduced a brilliant argument against materialism, but then changed him mind and concluded the argument failed. Personally, I think the first argument works, and the "latter Frank Jackson" is mistaken. As I noted, it is very hard to claim that either constancy or change (in the abstract) is good or bad, but perhaps it may be concluded that the tradition of philosophy and the current philosophical community is enriched by both philosophers who change their mind with great frequency (Bertrand Russell comes to mind; he held so many positions that one could not refer to an early and late Russell, but a multi-faceted Russell) and those whose work from youth through maturity and until death has been very stable (Roderick Chisholm certainly changed his mind on a number of issues, but overall there were constant themes throughout his brilliant career, e.g. non-materialistic views of the person and intentionality, foundationalism in epistemology, Platonist in metaphysics, a moral realist, and so on). I think we need both our Russells and Chisholms to have a healthy philosophical community.

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