Knowledge is derived from cognition, but cognition of strong gravity and avolitional motions in dreams appears meaningless. Although cognition is modelled as dynamic system, there is no model of mechanics for gravity and motion in dreams. Study was done to describe the cognition of strong gravity and avolitional motions in dreams, and to determine if phenomenology can be modelled with physical theories. The brain was modelled as device that interacts with the environment and Consciousness. Spatial Self is the attribute of Consciousness which moves, and feels forces in dreams. Narratives of gravity and motions experienced only in dreams were modelled with classical mechanics. Language, knowledge graph, narrative and thematic analyses were performed. Median age of 253 subjects was 24 years (50 % inter-quartile range, 21–25). Avolition motion themes were terminable and interminable free fall, falling into dark holes, flying, cessation of motion in dark places, inability to initiate motion, and vanishing. Proportion (95 % CI) of themes in terrestrial settings was 83 % (79–88), but 17 % (12–21) in extraterrestrial settings. Newtonian mechanics modeled 41 % of narratives, but general relativity mechanics modeled 59 %. Artificial intelligence generated meaningful summary of narratives. Vocabulary and semantics of general relativity narratives were statistically distinct. Newtonian and general relativity narratives were in distinct communities of knowledge graph. There is objective reality of cognition in dreams. Classical and quantum mechanics model strong gravity and avolitional motions in dreams. Thus, Consciousness perceives more themes of nature in dreams.