Ole Peters

1/
How can I put this?
"Expected utility maximizers don't maximize utility."

Why? Because utility is not usually an ergodic quantity in the mathematical models used by economists, and maximizing its expected value doesn't mean much in the real world. 

2/
I've written a blog post about this with @hulme_oliver, where we spell out the mathematics and give you an interactive app. 
Try it out for yourself. Maximizing expected utility destroys actual utility. 
https://ergodicityeconomics.com/2025/05/28/expected-utility-maximizers-dont-maximize-utility/

3/
What does that mean? 
I would say it means that this core concept of orthodox economics -- utility -- is meaningless and misleading. 
But don't take my word for it - this is known: empirically, expected-utility theory and its descendants like prospect theory etc don't work.

4/
That was established in an admirable effort by 4 economists, experts in expected-utility theory, who reviewed 8 decades of empirical work, concluding: 
"The power to predict out-of-sample is in the poor to non-existent range."

See "Risky Curves"
https://www.routledge.com/Risky-Curves-On-the-Empirical-Failure-of-Expected-Utility/Friedman-Isaac-James-Sunder/p/book/9781138096462 

5/
If you find this as interesting as I do, come along next week to listen to one of the authors, Duncan James, present the book and recent updates, in our EE seminar series:

https://ergodicityeconomics.com/event/seminar-duncan-james-risky-curves-new-results-and-future-directions/

6/
And, of course, have a look at our textbook, where we develop Ergodicity Economics, from the ground up. A fully functioning formal alternative to orthodox economic theory.
https://ergodicityeconomics.com/publications/