The paper introduces considerations about the categorical relationship between the functional equation model in mathematics and fundamental human question categories in philosophy and linguistics, thinking of them as semantic base vectors: is there a semantic relationship between these basic human questions and the equation model, and if so, then what kind? We explore this question, and arrive at a qualitative categorical relationship, where broadly F is answered by questions “What?”, “Where?”, “When?”, the X is answered by “Who?” and “How?”, and the Y is answered by the question “Why?”. The result, while simple, may help us to define the base vectors for mapping human semantic space, and to create intuitions on how to convert human perceptions and conceptions into formal mathematical problems. The result may be useful for obtaining and retaining simple human-understandability of world’s systems and processes; transforming semantic spaces to forms more conducive to human understanding; embedding sets of databases into the space of the semantic vectors by labeling tables, collections and entities with the question categories; creating database indices optimal for human interpretation and application of the equation model for information retrieval, machine learning, machine reasoning and search for actions to achieve goals.