A disposition is a quality of character, a habit, a preparation, a state of readiness, or a tendency to act in a specified way. The terms dispositional belief and occurrent belief refer, in the former case, to a belief that is held in the mind but not currently being considered, and in the latter case, to a belief that is currently being considered by the mind. In Bourdieu's theory of fields, dispositions are the natural tendencies of each individual to take on a specific position in any field. There is no strict determinism through one's dispositions. The habitus is the choice of positions according to one's dispositions. However, in retrospect, a space of possibles can always be observed. A disposition is not a process or event in some duration in time, but rather the state, preparation, or tendency of a structure "in waiting". In the field of possibilities, its actual triggering has a statistical value. Metaphysics The debate about dispositions in metaphysics attempts to understand the fundamental nature of properties, including how they relate to laws of nature. The initial question asks if dispositions are real. Realism about dispositions, or dispositionalism, argues that dispositions are causally efficacious properties inherent to objects that are sufficient to produce change. Consider fragility. If a glass is suitably struck, it will break. Fragility is a property of the glass that accounts for this breaking. Paradigmatic examples of dispositional properties include fragility, solubility, and flammability. Dispositionalism maintains that even paradigmatic examples of what appears to be qualitative such as squareness has causal powers (for instance - when combined with the property of hardness - to make a square impression in soft wax). This view is historically argued for by Aristotle and Leibniz. Contemporary proponents include Sydney Shoemaker, U.T. Place, Stephen Mumford, Alexander Bird, George Molnar, Brian Ellis. Others answer that dispositions are not real properties. Anti-realism about dispositions, or categorical, argues that dispositions are ontologically derivative of the interaction of categorical (or qualitative) properties and laws. Accordingly calling a glass fragile, is a useful shorthand for describing the potential interactions of its microstructure (a categorical property) and the laws of nature; dispositions are not additional elements of being. Since the microstructure and laws are enough to explain fragility, there is no causal role for a dispositional property, here fragility, to play. This view is historically argued for by Descartes, Boyle, Hume and the logical positivists.