Incomparability and Incommensurability in Choice: No Common Currency of Value?

Abstract

Models of decision-making typically assume the existence of some common currency of value, such as utility, happiness, or inclusive fitness. This common currency is taken to allow comparison of options and to underpin everyday choice. Here we explore the ideas that there is no universal value scale, that incommensurability of value pervades everyday choice, and hence that most existing models of decision-making in both economics and psychology are fundamentally limited. We propose an alternative approach. This alternative assumes that choice objects can only be compared with reference to specific but non-universal “covering values”. These covering values may reflect decision-makers’ goals, motivations, or current states. A complete model of choice must accommodate the range of possible covering values. We show that abandoning the common currency assumption in models of judgment and decision-making necessitates rank-based and heuristic models that contrast radically with conventional utility-based approaches. Moreover, the idea that there is no single common currency for object valuation parallels the idea, central to social choice theory, that the welfares of different individuals cannot be combined to represent the welfare of society overall. We note that if there is no universal value scale then Arrow’s Impossibility Theorem places severe bounds on the rationality of individual decision-making, and hence that there is a deep link between the incommensurability of value, inconsistencies in human decision-making, and rank-based coding of value. More generally, incommensurability raises the question of whether it will ever be possible to develop single-quantity-maximizing models of decision-making.

Conviction Narrative Theory: A theory of choice under radical uncertainty

“…Filing for divorce merges the pain of leaving behind shared history with the prospect of turning over a new leaf. These potential options are difficult to evaluate because these attributes are along almost totally unrelated dimensions that resist placement onto a common scale (Walasek & Brown, 2021). • Incomparable outcomes.…”

“…But so often, one object excels on one dimension while another object excels on another. When the attributes are incommensurable, trading off attributes across choice objects is necessary to make a choice, yet it is often unclear how to do so rationally (Walasek & Brown, 2021). For example, consider choosing between careers as a clarinetist or lawyer (Raz, 1986).…”

Fenneman et al.’s (2022) review of formal impulsivity models: Implications for theory and measures of impulsivity.

“…In retaining the realism of these tasks, researchers can vary the reward modality to identify which modalities’ temporal and information impulsivity measurements might correlate with those of other modalities. Research in this domain is still in its infancy, but as a guide, we may take Trope and Liberman’s (2010) construal level theory or Walasek and Brown’s (2021) concept of covering values (the higher order goals/standards against which objects are evaluated) as a starting point for generating hypotheses. Both of these approaches do not assume that everything can be compared on a single value scale (i.e., utility), but instead propose that many decisions and behaviors serve to attain overarching construals or covering values .…”

Narratives, probabilities, and the currency of thought

“…We are unsure that this is an advance over representing utilities. As Walasek and Brown (in press) forcefully demonstrate, the problem with utilities is shoving preferences into a one-dimensional common currency, as a scalar affective value would. CNT abandons this approach in favor of affect because affect is multidimensional, motivates action, and is an evolved system for adaptively dealing with real situations.…”