carnap wrote: ↑Sat May 26, 2018 3:07 pmBut first mathematics can be used to model physical phenomena it doesn't in itself describe nature
Logic doesn't itself describe mathematical theorems, but with some additional assumptions, the inference rules of logic can provide a coherent description of mathematics. There are just additional assumptions we need to make to allow mathematics to facilitate empirical descriptions, namely induction.
carnap wrote:and in fact the vast majority of mathematical theories are developed with no physical application in mind but rather theoretical reasons.
Intent does not govern capacity, and even if some mathematics cannot be used to describe some physical phenomenon, that doesn't invalidate the contributions of the rest.
carnap wrote:But mathematics is a formal system, you make assumptions and then you reason from those assumptions using specific inference rules.
Ethics takes those assumptions, some scientific and metaphysical assumptions, and some additional assumptions which fit the definition of morality and uses inference rules to reason about them.
carnap wrote:That is dramatically different that a set of propositions
A set of propositions we deduced from axioms and inference rules?
carnap wrote:And what physical phenomena do ethical propositions describe?
None, rather they give new meaning to certain empirical circumstances. Why do ethics, or anything for that matter which is consistent, have to describe a physical phenomenon? How could you even reason yourself to such a necessity without abstract ideas?
carnap wrote:Ultimately you can create ethical theories until you're blue in the face but nobody has to follow them.
Maybe you don't care about being a good person unless the universe mandates it, but I do (arbitrarily, like I would with any other desire), and not caring doesn't change anything but your own disposition.
carnap wrote:Okay you'll call them a "immoral person" but who cares?
People do for some reason.
carnap wrote:Unlike physical laws, there are no (natural) consequences for going against moral codes.
That's not a problem, but there are: there are physical changes in your body caused by any given thing. There are also no natural consequences for going against natural laws (for a different reason, obviously).
carnap wrote:You're ignoring the fact that these two theories have difference consequences and that is how the theories are being judged. Occam's razor doesn't apply here, you're not comparing theories of physical phenomena. Also it should be noted that Occam's razor isn't a logical rule, there is no purely logical reason why the simple theory would always be the more correct theory. Occam's razor is a normative preference.
You're right, sorry. I have an Occam's razor fetish
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