 In the last thirteen years of his life, Schutz was preparing a comprehensive phenomenology of the natural attitude, and one manuscript, edited by Richard Zaner, was posthumously published as Reflections on the Problem of Relevance, and another, co-authored by Thomas Luckmann, appeared as The Structures of the Life World. The former book distinguishes different sets of interests, or relevances: topical (which focus attention on themes), interpretive (which confer meanings on experiences or objects), and motivational. Such relevances often involve a subject, with more or less systematic interests, or relevances, interacting with the world, and from this interaction between subject and world, it becomes evident what is “of relevance” to an actor. These relevances, interdependent on each other and conjoined with one’s system of types or categories, constitute a stock of knowledge, which Schutz examines in terms of its genesis and structure. He further explores the meaning of one’s biographical situation, including types and relevances, one’s body, and the ontological constraints of space and time that, for instance, prevent one from being at certain places at certain times or compel one to wait (for salt to dissolve in water).