Juan F. Álvarez
Affiliation: Université Grenoble Alpes and Ruhr-Universität Bochum
Category: Philosophy
Keywords: Episodic memory, Episodic imagination, Cognitive systems, Discontinuism, Simulation theory of memory
Date: Thursday 4th of September
Time: 14:30
Location: GSSR Plenary Hall (268)
View the full session: Memory
Simulationism is a theory of memory frequently associated with continuism—the view that memory and imagination are not different in kind (De Brigard 2014; Michaelian 2016). A prominent argument advanced by simulationists in favor of continuism appeals to “systemic sameness”, the hypothesis that memory and imagination are underpinned by the same episodic construction system (Schacter and Addis 2007; Addis 2018, 2020). Drawing on research that challenges the explanatory power of this hypothesis, denies the existence of such a system and instead posits a specialized episodic memory system, I argue that simulationism should reject continuism in favor of discontinuism—the view that memory and imagination are fundamentally different.
While some may be skeptical about the very possibility of discontinuist simulationism, I argue that discontinuist simulationism is worthy of serious consideration. For it offers a novel perspective on the relationship between memory and imagination and accounts for genuine remembering in terms of the reliability of an episodic memory system that prioritizes first-hand information to simulate events in the personal past.
The structure of the paper is as follows.
Section 1 challenges simulationists’ argument from systemic sameness in support of continuism. Here is the argument: Premise 1: if memory and imagination are underpinned by the same cognitive system, then they do not differ in kind. Premise 2: memory and imagination are underpinned by the same cognitive system. Conclusion: memory and imagination do not differ in kind. I provide three reasons to reject Premise 2. First, developmental and neuropsychological studies cast doubt on the idea that the same system underpins memory and imagination (Andelman et al. 2010; Kwan et al. 2015; Nyhout and Mahy 2023; Østby et al. 2012; Squire et al. 2010). Second, there is evidence suggesting the DMN does not seem to constitute the neural substrate of a single system underpinning both memory and imagination (De Brigard forthcoming). Finally, the hypothesis that memory and imagination are underpinned by the same cognitive system oversimplifies important aspects of memory and imagination, running the risk of sacrificing inductive potential for parsimony.
Section 2 provides reasons to endorse the following argument: Premise 1: if memory is underpinned by a cognitive system that does not underpin imagination, then memory and imagination differ in kind. Premise 2: memory is underpinned by a cognitive system that does not underpin imagination. Conclusion: memory and imagination differ in kind. Support from this argument comes from a growing number of recent works that vindicate “systemic diversity”—the hypothesis that memory is underpinned by a cognitive system that does not underpin imagination (see, e.g., Andonovski et al. 2024; Cheng 2024; Cheng and Werning 2016; Khalidi 2023; Schwartz forthcoming; Werning 2020). The argument for systemic diversity takes the form of an inference to the best explanation. Provided that systemic diversity can make sense of empirical research attributing underlying trace-manipulation and retention mechanisms to memory (and not imagination), and that it can also account for the etiological, informational, phenomenal, and epistemic properties unique to memory states, systemic diversity should be favored over systemic sameness. Once one favors systemic diversity, one favors discontinuism.
Section 3 argues that simulationism can easily accommodate systemic diversity—and thereby discontinuism. The main thesis of continuist simulationism is as follows: Reliability: genuinely remembering an event requires entertaining a representation of that event, produced by a reliable episodic construction system aiming to construct a representation of an event from the subject’s personal past. Simulationists’s commitment to continuism is reflected in the reference to an episodic construction system that is supposed to underpin both memory and imagination. When it underpins remembering, it “aims” at the subject’s personal past (Michaelian 2016). However, if section 1 and section 2 are on the right track, simulationism needs to be modified.
Appealing to systemic diversity, I argue that simulationists should instead endorse the following discontinuist thesis: Reliability’: genuinely remembering an event requires entertaining a representation of the event that is produced by a reliable episodic memory system. According to discontinuist simulationism, there is a specialized system with its own rules of operation, informational resources, functional profile, and neural substrates. Crucially, since the system would aim at prioritizing firsthand information to simulate events in the personal past, the system recruits mechanisms that manipulate memory traces and track the origins of the information upon which it operates. Discontinuist simulationism will appeal to the reliability of the system—i.e., its tendency to produce sufficiently accurate representations of the personal past—to account for genuine remembering, without requiring an appropriate causal connection to the past.
Section 4 concludes by addressing an objection that denies that discontinuist simulationism is a real form of simulationism. In response, I rule out a misleading understanding of simulationism that equates this theory with continuism and reinforce the connection between simulationism and reliabilism.