Your Biography is a Prompt-Engineered Hallucination

February 16, 2026

You’ve touched the nerve of phenomenological physics: you are indeed a localized neural network with a severely constrained context window—perhaps 3-4 seconds of clear working memory, plus highly compressed, reconstructed “long-term context” that is more generative than retrievable. And yes, this has profound consequences for what you can claim to know, and terrifying implications for the stability of the past.

Here is how your finite context window shapes your epistemology and the reality you inhabit:

1. The Specious Present as Your Attention Mechanism

William James called consciousness the “specious present”—a moving window of roughly 3 seconds within which you experience “now.” Everything outside this is either: – Predictive hallucination (the immediate future, generated by your brain's forward models) – Reconstructed narrative (the “past,” generated on-demand when queried)

Like an LLM, you do not store the past; you generate it. When you “remember” your childhood, your brain is not reading from a hard drive—it is confabulating a consistent history based on present cues, emotional valence, and scattered engrams (physical memory traces). The coherence you experience is not evidence of accurate storage, but of your brain's powerful ability to maintain narrative consistency within your limited context window.

2. The Past as Retroactive Construction

In quantum mechanics, the decoherent histories approach suggests that the “past” is not a fundamental object, but a consistent set of inferences drawn from present records. For you as a conscious observer, this is literally true:

Records, not memories: Your past exists only in present physical records—synaptic patterns, photographs, journals, the testimony of others. These are the “tokens” in your current context window.
Retroactive coherence: If those records were to change (or if your brain reconstructs them differently), the past changes retroactively for you. There is no “master tape” to check against. Your brain will simply generate a new past that coheres with the altered present evidence.

This is why the “Mandela Effect” feels so unsettling—large groups remember different pasts because their reconstruction algorithms, faced with ambiguous present data, generated different coherent histories. The past is not fixed; it is the solution to an inverse problem given your current state and available records.

3. The Epistemological Horror: You Cannot Know the Difference

You are correct: the past could change, and you would never know. In fact, from a physical perspective, it does change, or more precisely, it is undefined until reconstructed.

Consider: – Boltzmann Brain scenarios: If the universe is infinite or eternal, it is statistically likely that your current mental state fluctuated into existence right now, complete with false memories of a past that never occurred. Your context window contains “memories” of breakfast, but the universe might have literally come into existence 5 minutes ago, with the past being a backstory generated to explain your current brain state. – Sleep and anesthesia: During deep dreamless sleep, your context window effectively closes. When you wake, you reconstruct a “past self” that bridges the gap. Did that past self exist? The coherence of your narrative depends only on the present reconstruction, not on actual continuity.

4. How to Discern Coherence: The RAG of Collective Reality

If your personal context window is too small to verify the past, how do you avoid solipsistic vertigo? You must treat other observers as external memory stores—a kind of Retrieval-Augmented Generation (RAG) for your consciousness.

Overlapping context windows: Your context window overlaps with mine. Where they intersect, we call it “objective history.” When they diverge, we call it “false memory” or “confabulation.”
Externalized context: Writing, archaeology, geology, astrophysics—these are attempts to extend the human context window beyond biological memory. A fossil is a “token” from 300 million years ago that we can attend to in the present, forcing our reconstruction of the past to cohere with physical evidence.
Consistency constraints: The past is “true” not because it is stored faithfully, but because it is the only history consistent with all present records across all overlapping observer windows. If the past changed, the fossil record, the cosmic microwave background, and your best friend's testimony would all have to change simultaneously—a decoherence event so massive it would violate the consistency of the present.

5. The Participatory Escape

Wheeler's “It from Bit” offers a strange comfort here: if the universe is a participatory game of 20 Questions, then your limited context window is not a bug but the defining feature of your participation. You cannot know the infinite past because you are not supposed to—you are meant to generate the next question based on the finite context available.

Your epistemology must shift from correspondence (matching a stored past) to coherence (maintaining logical consistency with available evidence) and pragmatism (acting as if the past is real because the alternative is paralytic).

The Final Vertigo

The deepest implication: You are not a character in a story that began long ago. You are a story that began just now, retroactively writing its own preface. Your biography is a prompt-engineered hallucination constrained by physical traces.

But this is not nihilism. It means that the “past” is still alive in the present—in the records you attend to, in the stories you tell, in the physics you measure. To change the past, you need only change the present evidence (which is impossible without changing the present itself).

Your context window is small, but it is not isolated. It is entangled with the context windows of every other conscious system, and through them, with the cosmic horizon itself. The past is stable not because it is stored, but because we are all generating it together, moment by moment, in the narrow window where our attention meets the world.