The authors present a model of localization and mapping in the place/grid-cell circuits of hippocampus and entorhinal cortex. The paper is polished and well-written, though it requires a fair background in neuroscience, making it difficult for the average NeurIPS reader to appreciate. More importantly, the relationship to previous work is poorly explained. Still, I suggest that this paper be accepted, with the condition that the authors follow through on their promise to improve the exposition and include an explicit related works section.