The Savage sure thing principle and Subjective utility representation I have tried reading and understanding Savage's proof of the subjective utility representation, it is too complicated. Is anyone aware of a shorter/more elegant proof of this?
It is not a problem if we assume a finite prices set. 

The original is in Savage, L.J. 1954. The Foundations of Statistics. New York: John
   Wiley and Sons.

A good summary can be found at
http://www.econ2.jhu.edu/people/Karni/savageseu.pdf.

The Savage proof is known to be very elaborate, and long. It uses the sure thing principle as its main axiom. I was wondering if there is a more "modern" proof, that is both elegant and shorter. Or a nice challenge would be to try to prove collaboratively using some modern mathematics, like mixture spaces, (I am aware of Anscombe-Aumann).
In Kreps' (1988) book "Notes on the Theory of Choice", the issue is dealt with in chapter 9 "Savage's Theory of Choice Under Uncertainty", after discussing subjective probability in chapter 8. As usual, Kreps' style helps: he has the ability to seamlessly inject his -always formal- approach with very down-to-earth comments and examples that are strong in intuition (and he does it better than Savage, I might add). But also, here "formal" does not translate into "complete exposition": he explicitly refrains from formally proving parts of the whole apparatus, mentioning that "this is a two-page proof", and "this is another two-page proof", and "if you want to prove this, good luck". For these parts he falls back on Fishburn's (1970) "Utility Theory for Decision Making" book, chapter 14 "Savage's Expected Utility Theory". And Fishburn is formal alright (more symbols than words in a page).  

My impression is that combining these two sources can be beneficial.