Memory as the origin of the past: a developmental and conceptual refinement of the dependency thesis

This paper aims to refine the dependency thesis, which posits that episodic memory is necessary for acquiring the concept of pastness. By incorporating the hybrid concept thesis, which holds that pastness involves an irreducible experiential component, and the communicability constraint, which states that such experiential content cannot be acquired purely through linguistic or inferential means, this paper argues that pastness cannot be fully explained by relational properties alone. Developmental psychological evidence suggests that temporal cognition progresses in stages, with an early categorical sense of pastness emerging before the ability to structure time sequentially. At this early stage, individuals lack the capacity for time-place indexing, which reinforces the need for direct experiential access in forming the concept of the past. This structured framework clarifies why empirical objections—such as amnesia cases used to challenge the necessity of episodic memory—fail to undermine the dependency thesis. While patients with episodic memory loss retain some relational understanding of time, their concept of pastness remains indirectly dependent on the episodic memory of others. Similarly, critiques arguing that episodic memory is not sufficient for past concept formation conflate different stages of cognitive development, overlooking the necessity of early direct experiential awareness. By integrating philosophical and psychological insights, this paper provides a structured argument for the specific way in which episodic memory contributes to our understanding of time.