Abstract
When reading a novel or poem, readers sometimes gain comprehension or experiences that cannot be expressed in language yet are felt as holistic. Previous studies focused on the linguistically expressible aspects of text comprehension. In this study, we propose a new hypothesis, the purification comprehension hypothesis, that seeks to explain how a reader constructs indescribable and coherent comprehension using quantum probability theory. This hypothesis regards the reading process as purification, in which the reader's initial interpretation state is mixed, and the reader incorporates external systems, such as the interpretation of other parts of the text or prior knowledge, to purify their state. Therefore, the dimensionality of the state increases and von Neumann entropy decreases through purification. We also highlight two types of reading based on this hypothesis: purification and deterministic. Our model contributes to studies on reading by bridging humanities and scientific studies, provides implications for cognition models that aim to minimize Shannon entropy, and has the potential to apply cognition related to other modalities and media, such as music and art.