When the discount factors that infinite lived consumers use at each date are not predetermined but are instead chosen within some set, depending on what the consumption plan is, impatience might not hold. More precisely, if the utility is the infimum of discounted utilities over that set of discount factor sequences, then preferences may be just upper semi-impatient. Such lack of lower semi-impatience, which we refer to as wariness, consists in neglecting distant gains but not distant losses. Examples are the precautionary case (a concern with the worst lifetime outcome) and the habit persistence case (a concern with a fall in living standards). The implementation of efficient allocations by trading assets sequentially requires taxes that avoid excessive savings by raising the opportunity of cost of saving up to the point of matching the marginal benefit of dishoarding at distant dates. Taxes on equilibrium plans are zero in many contexts. 

https://doi.org/10.1016/j.jet.2019.07.004

More and more economists are finding both empirical and experimental evidence of economic behavior that is well beyond classical economics. In particular, empirical evidence (Jullien and Salanié (2000)) and experimental evidence (Kahneman and Tversky (1979)) supported the importance of risk loving, ambiguity loving, and related behavior in economics. However, these types of preferences have not been analyzed in the general equilibrium literature with a finite number of agents because non‐convexity of preferences creates difficulty in proving existence of equilibrium. The main result in this paper provides a set of conditions under which equilibrium exists in such economies. 

https://doi.org/10.3982/ECTA14777

We prove that under mild conditions individually rational Pareto optima will exist even in the presence of non-convex preferences. We consider decision-makers (DMs) dealing with a countable flow of pay-offs or choosing among financial assets whose outcomes depend on the realization of a countable set of states of the world. Our conditions for the existence of Pareto optima can be interpreted as a requirement of impatience in the first context and of some pessimism or not unrealistic optimism in the second context. A non-existence example is provided when, in the second context, some DM is too optimistic. We furthermore show that at an individually rational Pareto optimum at most one strictly optimistic DM will avoid ruin at each state or date. Considering a risky context, this entails that even if risk averters will share risk in a comonotonic way as usual, at most one classical strong risk lover will avoid ruin at each state or date. Finally, some examples illustrate circumstances when a risk averter could take advantage of sharing risk with a risk lover rather than with a risk averter.

https://doi.org/10.1007/s00199-016-0985-0

Wary consumers overlook gains but not losses in remote sets of dates or states. As preferences are upper but not lower Mackey semi-continuous, Bewleyʼs (JET, 1972) result on existence of equilibrium whose prices are not necessarily countably additive holds. Wariness is related to lack of myopia and to ambiguity aversion (and, therefore, to Bewleyʼs (1986) work on Knightian uncertainty). Wary infinite lived agents have weaker transversality conditions allowing them to be creditors at infinity and for bubbles to occur in positive net supply assets completing the markets. There are efficient allocations that can only be implemented with asset bubbles. 

https://doi.org/10.1016/j.jet.2011.01.005