Johannes, B. Mahr

Do any nonhuman animals have hedonically valenced experiences not directly caused by stimuli in their current environment? Do they, like us humans, experience anticipated or previously experienced pains and pleasures as respectively painful and pleasurable? We review evidence from comparative neuroscience about hippocampus-dependent simulation in relation to this question. Hippocampal sharp-wave ripples and theta oscillations have been found to instantiate previous and anticipated experiences. These hippocampal activations coordinate with neural reward and fear centers as well as sensory and cortical areas in ways that are associated with conscious episodic mental imagery in humans. Moreover, such hippocampal “re- and preplay” has been found to contribute to instrumental decision making, the learning of value representations, and the delay of rewards in rats. The functional and structural features of hippocampal simulation are highly conserved across mammals. This evidence makes it reasonable to assume that internally triggered experiences of hedonic valence (IHVs) are pervasive across (at least) all mammals. This conclusion has important welfare implications. Most prominently, IHVs act as a kind of “welfare multiplier” through which the welfare impacts of any given experience of pain or pleasure are increased through each future retrieval. However, IHVs also have practical implications for welfare assessment and cause prioritization.

Episodic representations can be entertained either as “remembered” or “imagined”—as outcomes of experience or as simulations of such experience. Here, we argue that this feature is the product of a dedicated cognitive function: the metacognitive capacity to determine the mnemicity of mental event simulations. We argue that mnemicity attribution should be distinguished from other metacognitive operations (such as reality monitoring) and propose that this attribution is a “cognitive gadget”—a distinctively human ability made possible by cultural learning. Cultural learning is a type of social learning in which traits are inherited through social interaction. In the case of mnemicity, one culturally learns to discriminate metacognitive “feelings of remembering” from other perceptual, emotional, action-related, and metacognitive feelings; to interpret feelings of remembering as indicators of memory rather than imagination; and to broadcast the interpreted feelings in culture- and context-specific ways, such as “I was there” or “I witnessed it myself.” We review evidence from the literature on memory development and scaffolding, metacognitive learning and teaching, as well as cross-cultural psychology in support of this view before pointing out various open questions about the nature and development of mnemicity highlighted by our account.

The question of what the function of human remembering might be has entered the contemporary philosophical discourse only relatively recently. In this debate, two main views have emerged: preservatism and simulationism. According to preservatism, the function of remembering is to preserve information from/about the past. In contrast, simulationism holds that the function of remembering is to enable reliable thought about the future. Here, I employ form to function reasoning to evaluate both of these views. I argue that both perservatism and simulationism fail to account for the entire representational structure of episodic remembering. As an alternative, I then propose my own account: that the function of remembering is to track when we have epistemic authority about the past.

Human adults possess the extraordinary ability to produce mental imagery about a wide variety of non-occurrent events. We can, for example, simulate the perception of different places, different times, different possibilities, or others’ perspectives. Findings from cognitive psychology, neuropsychology, and cognitive neuroscience suggest that all of these capacities rely on the same neuro-cognitive mechanism: episodic simulation. This ability produces mental imagery by constructively recombining elements of past experiences to simulate event representations. However, if episodic simulation indeed produces mental imagery, it remains unclear how the non-imagistic aspects of its outputs become cognitively determined. In this article, I argue that there are (at least) four such non-imagistic ‘dimensions’ of episodic simulation: specificity, temporal orientation, subjectivity, and factuality. Further, I propose an account of the mechanisms which might be responsible for determining where a given output of episodic simulation falls within this dimensional space. According to this view, episodic simulation relies on propositional ‘scope-operators’ either deployed as inputs to the simulation process itself or produced by post-hoc monitoring processes operating over its outputs. This view has consequences for how we should view the operation, development, and evolution of episodic simulation.

The past is undeniably special for human beings. To a large extent, both individuals and collectives define themselves through history. Moreover, humans seem to have a special way of cognitively representing the past: episodic memory. As opposed to other ways of representing knowledge, remembering the past in episodic memory brings with it the ability to become a witness. Episodic memory allows us to determine what of our knowledge about the past comes from our own experience and thereby what parts of the past we can give testimony about. In this article, we aim to give an account of the special status of the past by asking why humans have developed the ability to give testimony about it. We argue that the past is special for human beings because it is regularly, and often principally, the only thing that can determine present social realities such as commitments, entitlements, and obligations. Because the social effects of the past often do not leave physical traces behind, remembering the past and the ability to bear testimony it brings is necessary for coordinating social realities with other individuals.

Episodic memory has been analyzed in a number of different ways in both philosophy and psychology, and most controversy has centered on its self-referential, autonoetic character. Here, we offer a comprehensive characterization of episodic memory in representational terms and propose a novel functional account on this basis. We argue that episodic memory should be understood as a distinctive epistemic attitude taken toward an event simulation. In this view, episodic memory has a metarepresentational format and should not be equated with beliefs about the past. Instead, empirical findings suggest that the contents of human episodic memory are often constructed in the service of the explicit justification of such beliefs. Existing accounts of episodic memory function that have focused on explaining its constructive character through its role in future-oriented mental time travel do justice neither to its capacity to ground veridical beliefs about the past nor to its representational format. We provide an account of the metarepresentational structure of episodic memory in terms of its role in communicative interaction. The generative nature of recollection allows us to represent and communicate the reasons why we hold certain beliefs about the past. In this process, autonoesis corresponds to the capacity to determine when and how to assert epistemic authority in making claims about the past. A domain where such claims are indispensable are human social engagements. Such engagements commonly require the justification of entitlements and obligations, which is often possible only by explicit reference to specific past events.

The ‘frame problem’ according to Jerry Fodor concerns the question of how a cognitive system like ours can frugally and reliably determine what is relevant for its processing tasks. A number of authors have pointed to heuristics as a solution to this question. A heuristic solution, however, leaves unanswered important epistemological problems concerning the rationality and truthfulness of human cognition. In this dissertation I will try to address these ‘epistemological relevance problems’ on the basis of a heuristic account of reasoning. Thereby, I will argue that we need to look beyond internal computational processes to our technological and social wherewithal to understand the characteristic success humans have enjoyed in their epistemic endeavours. More concretely, it will be my claim that collaborative reasoning allows us to enter a cumulative selection process in the direction of optimal solutions.