It's a bit disconcerting how a community, priding itself on consequentialist reasoning and rationality, so quickly reverts to using flimsy reasoning to justify the same decision they would have made before adopting such a worldview.
I'm not disagreeing with this decision, of course -- I've corrected bartenders several times when they undercharge me by leaving off a drink, and I've returned to a store to pay for a $50 item they didn't charge me for. (And I've been the recipient of the kindness of a co-worker who found a $100 bill I had dropped but had given up on finding.)
My point is that a lot of discussion here of ethics-as-practiced gives off this vibe of, "Don't worry, we can be moral like non-rationalists, really -- we even leave holes in our otherwise uncompromising reasoning to avoid becoming jerks! ('dicks')"
A few questions for those who have an answer to this dilemma:
The proffered justifications here seem to attempt to sidestep these unavoiable questions, and don't attempt to apply the insights discussed and sequence'd here regarding decision theory and ethics.
My answer (rot13): Cre zl rzcunfvf ba npnhfny naq fhowhapgvir zrnaf raqf yvaxf (gung Qerfpure gnyxf nobhg va Tbbq naq Erny, be V qb va zl negvpyr "Zbenyvgl nf Cnesvgvna-Svygrerq Qrpvfvba Gurbel"), V ernfba nf sbyybjf: vs V qvq abg ertneq vg nf bcgvzny gb znxr fbzr rssbeg gb trg gur zbarl onpx gb vgf bjare, arvgure jbhyq bguref ertneq vg nf bcgvzny gb qb gur fnzr sbe zr, jrer gur ebyrf erirefrq. Npgvat onfrq ba gur onfvf bs guvf qlnanzvp zrnaf gung V jvyy svaq zlfrys va n jbeyq jvgu zber fhpu trareny xvaqarff, rira gubhtu fhpu npgvbaf jvyy abg pnhfr orggre pbafrdhraprf sbe zr. Guvf ernfbavat vf cnenyyry gb gur whfgvsvpngvba sbe jul bar fubhyq bar-obk va Arjpbzo'f ceboyrz be cnl va Cnesvg'f Uvgpuuvxre -- V pnaabg cbvag gb n orarsvg gb zlfrys gung V pnhfr, ohg V jbhyq cersre gung V npgrq cre na nytbevguz gung unq gubfr nf na bhgchg.
In this situation, and most commonplace situations, your decision theory still roughly summarizes to "not being a dick".
That not-being-a-dick can be subsumed into a more general acausal decision theory, is much like the way Newtonian physics was subsumed into Einsteinian physics.
Newtonian physics will still give you a mostly correct answer in most commonplace situations for normal human beings. And so will the not-being-a-dick decision theory for the commonplace situation described in the post above. And much like Newtonian equations over Einsteinian ones, it's often easier for human minds to calculate.
I just found 120 Euro (about $172) on the floor in the hallway in a hostel in Berlin. What should I do, and why?