# What exactly does "carriers of utility" mean?

I understand what 'utility' mean in economics.

While reading "Choices, Values, and Frames" by Daniel Kahneman I encountered above usage. I guess it means 'what utility is attributed to'. Google showed that this usage is common in economics literature, but I couldn't find a definition or an explanation.

What is the definition, if there is one? And if not, how best to interpret this phrase?

(Edit) Examples: From above book (p-xii):

• The proposition that the carriers of utility are states of wealth is accepted as a matter of course in economic analyses and in the prescriptions of decision analysis.
• The idea that the effective carriers of utility are gains and losses was not now.

In "Decision, Probability and Utility: Selected Readings" by Peter Gärdenfors and Nils-Eric Sahlin:

• As regards the conceptualization of utility, a fundamental question is what kids of entities can be assigned utilities. Or in other words, what are the carriers of utility? ...
• Can you please cite the sentence as a whole in order to provide us a meaningful context? Jan 11 '16 at 8:28
• I think your intuition is correct. If we were to define it formally, say we have a set of agents, $I$, and a set of objects/goods, $X$. We would say object $x$ is a carrier of utility if there exists an $i \in I$ such that $u_i(x)>0$. Do others agree? Jan 11 '16 at 15:16

For instance, saying that the carrier of utility for John is the difference between John's wealth and Lisa's wealth means that the utility function of John is of the form $u(x-y)$ where $x$ is John's wealth and $y$ is Lisa's wealth. It is another way of saying that the only thing that matters to John is his relative wealth compared to Lisa, and not his absolute wealth.