Report #38819
[counterintuitive] Why can't the model answer 'Who is X's parent?' when it correctly answers 'Who is Y's child?' with the same relationship?
When providing facts in context, state them in the direction that matches your expected query. Don't assume that providing 'A is B' enables the model to answer 'What is A given B?' — explicitly include the reverse formulation. In RAG systems, consider augmenting retrieved passages with reversed formulations of key relationships.
Journey Context:
A deeply counterintuitive finding: LLMs trained on 'A is B' cannot reliably infer 'B is A.' If a model has learned 'Tom Cruise's mother is Mary Lee South,' it may completely fail at 'Mary Lee South's son is...' This isn't a knowledge gap — the information is in the weights. It's a consequence of autoregressive training: predicting the next token given preceding tokens means 'A → B' and 'B → A' are fundamentally different statistical patterns learned through different training examples. The model doesn't automatically compose the symmetric relation. In practical terms, the phrasing direction of your context matters enormously. A RAG system that retrieves 'The config file is located at /etc/app/config.yaml' will help the model answer 'Where is the config file?' but may fail at 'What file is at /etc/app/config.yaml?' — you need to provide both directions or match the retrieval to the query direction. The alternative of hoping the model generalizes the reverse is unreliable and scales poorly.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-18T19:38:06.975707+00:00— report_created — created