I am not a true utilitarian, so this would be affected by the likelihood that the person I picked was of greater importance to me (causing a higher number of utils be gained/lost for fun/torture, respectively) than a random stranger.
You needn't value all people equally to be a true utilitarian, at least in the sense the word is used here.
...really happy people (RHP) who experience, by default, 150 Fun Units (funU) per month, happy people (HP) who experience 100 funU/mo by default, and sad people (SP) who experience only 50 funU/mo by default. ... being tortured means that you lose all of your fun...
I think you are seriously underestimating torture by supposing that the difference between really happy (top 5% level) and sad (bottom 25% level) is bigger than between sad and tortured. It should rather be something like: really happy 100 U, happy 70 U, sad 0 U, tortured -3500 U.
You needn't value all people equally to be a true utilitarian, at least in the sense the word is used here.
Really? Is all I need to do to be a utilitarian is attach any amount of utility to other peoples' utility function and/or feelings?
I think you are seriously underestimating torture by supposing that the difference between really happy (top 5% level) and sad (bottom 25% level) is bigger than between sad and tortured. It should rather be something like: really happy 100 U, happy 70 U, sad 0 U, tortured -3500 U.
Uh, oops. I'm thinking that I could ...
Most of the usual thought experiments that justify expected utilitarialism trade off fun for fun, or suffering for suffering. Here's a situation which mixes the two. You are offered to press a button that will select a random person (not you) and torture them for a month. In return the machine will make N people who are not suffering right now have X fun each. The fun will be of the positive variety, not saving any creatures from pain.
1) How large would X and N have to be for you to accept the offer?
2) If you say X or N must be very large, does this prove that you measure torture and fun using in effect different scales, and therefore are a deontologist rather than a utilitarian?