The fearful ape hypothesis (FAH) presents an evolutionary-developmental framework stipulating that in the context of cooperative caregiving, unique to human great ape group life, heightened fearfulness was adaptive. This is because from early in human ontogeny fearfulness expressed and perceived enhanced care-based responding and cooperation with mothers and others. This response extends and refines the FAH by incorporating the commentaries' suggestions and additional lines of empirical work, providing a more comprehensive and nuanced version of the FAH. Specifically, it encourages and hopes to inspire cross-species and cross-cultural, longitudinal work elucidating evolutionary and developmental functions of fear in context. Beyond fear, it can be seen as a call for an evolutionary-developmental approach to affective science.

Conviction Narrative Theory (CNT) is a theory of choice under radical uncertainty – situations where outcomes cannot be enumerated and probabilities cannot be assigned. Whereas most theories of choice assume that people rely on (potentially biased) probabilistic judgments, such theories cannot account for adaptive decision-making when probabilities cannot be assigned. CNT proposes that people use narratives – structured representations of causal, temporal, analogical, and valence relationships – rather than probabilities, as the currency of thought that unifies our sense-making and decision-making faculties. According to CNT, narratives arise from the interplay between individual cognition and the social environment, with reasoners adopting a narrative that feels “right” to explain the available data; using that narrative to imagine plausible futures; and affectively evaluating those imagined futures to make a choice. Evidence from many areas of the cognitive, behavioral, and social sciences supports this basic model, including lab experiments, interview studies, and econometric analyses. We identify 12 propositions to explain how the mental representations (narratives) interact with four inter-related processes (explanation, simulation, affective evaluation, and communication), examining the theoretical and empirical basis for each. We conclude by discussing how CNT can provide a common vocabulary for researchers studying everyday choices across areas of the decision sciences.

To fully embrace situations of radical uncertainty, we argue that the theory should abandon the requirements that narratives, in general, must lead to affective evaluation, and that they have to explain (and potentially simulate) all or even the bulk of the current decisional context. Evidence from studies of incidental learning show that narrative schemata can bias decisions while remaining fragmentary, insufficient for prediction, and devoid of utility values.

Conviction Narrative Theory bears a close resemblance to the Theory of Narrative Thought, although the two were designed to address different questions. In this commentary, we detail some of the more pronounced similarities and differences and suggest that resolving the latter could produce a third theory of narrative cognition that is superior to either of these two.

We challenge Johnson et al.'s assumption that people reduce unclear situations to a single narrative explanation and that such reduction would be adaptive for decision-making under radical uncertainty. Instead, we argue that people imagine and maintain multiple narrative possibilities throughout the decision-making process and that this process provides cognitive flexibility and adaptive benefits within the proposed model.

Conviction Narrative Theory (CNT) is a convincing descriptive theory, and Johnson et al.'s formal model is a welcome contribution to building more precise, testable hypotheses. However, some extensions to the proposed model would make it better defined and more powerful. The suggested extensions enable the model to go beyond CNT, predicting choice outcomes and explaining affective phenomena.

Focusing on imagination and the social context in the generation of conviction narratives, we propose that these elements are dynamically related to one another, and crucially that it is the nature of this relationship that determines individuals' level of epistemic openness and capacity to respond adaptively to update their narratives in a way that increases the possibility of more successful decision-making.

Johnson et al. suggest that we rely on narratives to make choices under radical uncertainty. We argue that in its current version Conviction Narrative Theory (CNT) does not account for embodied, direct sensorimotor influences on choices under radical uncertainty that may bypass narratives, particularly in highly time-constrained situations. We therefore suggest to extend CNT by an embodied choice perspective.

Johnson et al. make a persuasive case that qualitative, story-like reasoning plays a crucial role in everyday thought and decision-making. This commentary questions the cohesiveness of this type of reasoning and the representations that generate it. Perhaps narratives do not underpin, but are ephemeral products of thought, created when we need to justify our actions to ourselves and others.

A significant body of literature has identified how narrative provides a basis for perceiving and understanding human experience. In the target article, the authors arrive at the need for a form of narrative-based reasoning due to constraints that render probabilistic-based reasoning ineffective. This commentary attempts to bridge this gap and identify links between the proposed and existing theories.

Simulation – imagining future events – plays a role in decision-making. In Conviction Narrative Theory, people's emotional responses to their simulations inform their choices. Yet imagining one possible future also increases its plausibility and accessibility relative to other futures. We propose that the act of simulation, in addition to affective evaluation, drives people to choose in accordance with their simulations.

Johnson, Bilovich, and Tuckett set out a helpful framework for thinking about how humans make decisions under radical uncertainty and contrast this with classical decision theory. We show that classical theories assume so little about psychology that they are not necessarily in conflict with this approach, broadening its appeal.

I enjoyed reading this compelling account of Conviction Narrative Theory (CNT). As a theoretical neurobiologist, I recognised – and applauded – the tenets of CNT. My commentary asks whether its claims could be installed into a Bayesian mechanics of decision-making, in a way that would enable theoreticians to model, reproduce and predict decision-making.

Narratives and heuristics are both tools for dealing with uncertainty, intractability, and incommensurability, that is, for all real-world situations outside the domain of Bayesian decision theory. But how do narratives and heuristics relate? I suggest two links: Heuristics select narratives to explain events, and “big” narratives select the heuristics that people live by, to execute their values and moral principles.

The case for the superiority of Conviction Narrative Theory (CNT) over probabilistic approaches rests on selective employment of a double standard. The authors judge probabilistic approaches inadequate for failing to apply to “grand-world” decision problems, while they praise CNT for its treatment of “small-world” decision problems. When both approaches are held to the same standard, the comparative question is murkier.

Human lives are radically uncertain. Making sense of such uncertainties is the hallmark of wisdom. Sense-making requires narratives, putting them in the center stage of human everyday decision-making. Yet what if radical uncertainty is a narrative itself? Moreover, do laypeople always consider such narratives irrational? Here we pose these questions to enrich a theory of choice under uncertainty.

While Conviction Narrative Theory correctly criticizes utility-based accounts of decision-making, it unfairly reduces probabilistic models to point estimates and treats affect and narrative as mechanistically opaque yet explanatorily sufficient modules. Hierarchically nested Bayesian accounts offer a mechanistically explicit and parsimonious alternative incorporating affect into a single biologically plausible precision-weighted mechanism that tunes decision-making toward narrative versus sensory dependence under varying uncertainty levels.

By structuring information in a systematic relational framework, narratives are cultural attractors that are particularly well-suited for transmission. The relational structure of narrative is partly what communicates causality, but this structure also complicates both transmission and selection on cultural elements by introducing correlations among narrative elements and between different narratives. These correlations have implications for adaptation, complexity, and robustness.

Conviction Narrative Theory is an interesting and plausible way to think about how individuals make decisions when quantitative assessments are not open to them. The question I pose is the following. Is there any general result about how decisions should be taken independent of the particular circumstances of that decision?

Johnson et al. make a strong case for Conviction Narrative Theory, but it remains unclear why so many adaptive narratives include supernatural causes and other falsehoods. Focusing on religions, I argue that an adaptive decision-making system might include supernatural falsehoods because they simplify complex problems, they are sensitive to long-term incentives, and they evoke strong emotions in a communicative context.