Comment on Average utilitarianism must be correct?

Sat, 15 Feb 2014 22:05:42 GMT

Here's what I mean, roughly expressed. Two possible timelines.
(A)

2010 Alice loves her life (she wants to live with continued life being a preference satisfaction of 7 per year). Bob merely likes his life (he wants to live with continued life being a preference satisfaction of 6 per year).

2011 Alice and 2011 Bob both alive as before.

2012 Alice and 2012 Bob both alive as before.

2013 Alice and 2013 Bob both alive as before.

2010 Bob wants 2010 Bob to exist, 2011 Bob to exist, 2012 Bob to exist, 2013 Bob to exist.
2010 Alice wants 2010 Alice to exist, 2011 Alice to exist, 2012 Alice to exist, 2013 Alice to exist.

2010 average utility is therefore (4x7 + 4x6) / 2= 26 and that also remains the average for the whole timeline.

(B)

2010 Alice and Bob same as before.

2011 Alice is alive. Bob has just been killed.

2012 Alice alive as before.

2013 Alice alive as before.

2010 average utility is: 4x7 +6 = (4x7 + 1x6)/2 = 17
2011 average utility is: 4x7 = 28
2012 average utility is: 4x7 = 28
2013 average utility is: 4x7 = 28

So Bob's death increased the average utility indicated in the preferences of a single year. But average utilty across the timeline is now (28 + 6 + 28 + 28 + 28) / 5 = 23.6

In short the average utility of the timeline as a whole is decreased by taking out Bob.

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