I’ve recently published a document exploring a subtle but critical design limitation in large language models — their inability to perceive or reason about real-world time.
The core issue:
LLMs generate time-related language (“now,” “yesterday,” “later”) without any access to system clocks, timestamps, or temporal state — and yet, the output often appears contextually correct.
This causes a dangerous mismatch between:
Human expectations (AI must “know” the time, it’s a system after all), and
Model design (time is deliberately excluded to preserve security and determinism).
Why this matters:
Developers may incorrectly assume “contextual fluency = temporal understanding”
Users often trust AI-generated timestamps or event ordering without verifying
Memory pipelines and multi-agent systems may silently break without time grounding
The document explores:
Real-world examples (e.g. ChatGPT suggesting “evening tea” during a Japan morning)
Why models can’t access or manage time (security + determinism)
How training bias favors plausible language over truthful sequence
What users and developers should be aware of when trusting time-related outputs
English README.md:
English version:
Japanese original:
Would love to hear feedback — especially from those working on memory, agent chaining, or multimodal LLMs.