Et potensielt problem med ordinale preferanser

When it was conclusively shown that large segments of economic thought could be maintained by postulating merely an ordinal preference pattern – an ordering – for alternatives without including an underpinning of latent «utiles,» the utility notion was not worth philosophizing about. Still one may contend that introducing numbers does no harm, that they summarize the ordinal data in a compact way, and that they are mathematically convenient to manipulate. But, in part, their very manipulative convenience is a source of trouble, for one must develop an almost inhuman self-control not to read into these numbers those properties which numbers usually enjoy. For example, one must keep in mind that it is meaningless to add two together or to compare magnitudes of differences between them.

– Luce og Raiffa (1957)

Det Luce og Raiffa her peker på tas ofte som en selvsagthet. Ordinale preferanser er ikke det samme som kardinale preferanser. Om man faktisk har tilegnet seg denne «nærmest umenneskelige selvkontrollen» som nevnes, er det allikevel svært viktig å være klar over at de aller fleste som ikke godt kjent med spillteori eller lignende metoder leser tall slik de er vant til; tall kan summeres, tall sier noe om forhold osv.