Problem Statement

Digital files are traditionally organized by place: folders, directories, and storage locations. Yet human memory does not work this way. People remember context, moments, and experiences — not physical or digital locations.

Several recurring challenges:

1. Files exist in isolation with no clear links between related content.
2. Related files are scattered across folders, apps, and formats.
3. Versioning creates chaos, with multiple copies and inconsistent naming making it hard to track progress.
4. The creative process disappears — iteration, exploration, and decision-making leave no visible trace, making it difficult to revisit or understand past work.
5. Together, these issues make revisiting files slow, confusing, and disconnected from how people actually remember their work.

Theoretical Foundation

Human Memory & Temporal Encoding

The central premise of macOS Timeline is grounded in Tulving's (1972) foundational distinction between episodic and semantic memory. Tulving established that humans encode experiences temporally, remembering when things happened relative to other events rather than categorically. This finding directly motivates replacing hierarchical folder navigation with a time-ordered interface. Where traditional file systems require users to remember where they stored something, a timeline interface aligns with how memory actually works: recalling the moment a file was created or last used, rather than its location.

Godden and Baddeley's (1975) research on context-dependent memory further supports the intersection search feature. Their finding that information is recalled better when the retrieval context matches the encoding context explains why searching by co-occurring events (the app open alongside a document, the song playing during a session) is more cognitively natural than keyword-only search.

The Limits of Spatial File Organization

Malone's (1983) study of how people organize their desktops found that even users who deliberately create folder hierarchies resort to temporal memory when searching for files, recalling items by when they worked on them rather than where they stored them. This tension between spatial organization and temporal recall is precisely the problem macOS Timeline addresses.

Jones, Bruce, and Dumais (2001) extended this finding to web browsing, observing that users frequently cannot remember where they filed things and default to temporal cues. Together, these studies establish that the folder metaphor is not a natural cognitive fit for most users, and that time-based retrieval is a more reliable mental model.

Ideation

Concept — Three Connected Solution Ideas

Documents as Living Entities

Each document is treated as a continuous, living object, containing all versions, edits, and branches in a single place. Rather than creating multiple files for iterations, a document evolves over time, preserving the creative process. Users can view the document’s full history, see how ideas developed, revisit past ideas, compare changes without losing context.

Contextual Linking

Instead of relying on folders or manual organization, documents form connections based on how they are used together. Each time two or more files are opened or edited in the same context, a link is created and strengthened over time. These relationships allow documents to self-group naturally, reflecting real workflows rather than artificial folder structures. The grouped files exist in dynamic spaces that emerge from activity and shared metadata, making it easy to discover related content, navigate projects intuitively, and see the relationships between files that were previously invisible.

Search Through Context

Your memory works by context, not filenames. Intersectional Search lets you find any document by stacking filters: the app you had open, the song you were listening to, or the meeting it was tied to. The more context you add, the more precise your results.

Video

Privacy Note

A common first reaction is to compare this to Microsoft's Recall, which continuously screenshots user activity and processes it through an on-device AI model. That approach creates a searchable visual record of everything on screen, including passwords, private messages, and sensitive documents, raising serious privacy and security concerns. This project takes a fundamentally different approach. It works with metadata only: which app was in focus, which file was open, what song was playing, and when. No screen content is captured, stored, or analyzed. The result is a lightweight temporal index rather than a surveillance log, offering the same navigational benefits of time-based retrieval without exposing private information.

References

Godden, D. R., & Baddeley, A. D. (1975). Context-dependent memory in two natural environments: On land and underwater. British Journal of Psychology, 66(3), 325-331.

Jones, W., Bruce, H., & Dumais, S. (2001). Keeping found things found on the web. Proceedings of CIKM '01.

Malone, T. W. (1983). How people organize their desktops. ACM Transactions on Office Information Systems, 1(1), 99-112.

Tulving, E. (1972). Episodic and semantic memory. In E. Tulving & W. Donaldson (Eds.), Organization of Memory. Academic Press.