The Assumption of Determinism

Because a main goal of science is to discover lawful relationships, science assumes that what is being investigated is lawful. For example, the chemist assumes that chemical reactions are lawful, and the physicist assumes that the physical world is lawful. The assumption that what is being studied can be understood in terms of causal laws is called determinism. Taylor (1967) defined determinism as the philosophical doctrine that “states that for everything that ever happens there are conditions such that, given them, nothing else could happen”. The determinist, then, assumes that everything that occurs is a function of a finite number of causes and that, if these causes were known, an event could be predicted with complete accuracy. However, knowing all causes of an event is not necessary; the determinist simply assumes that they exist and that as more causes are known, pre- dictions become more accurate. For example, almost everyone would agree that the weather is a function of a finite number of variables such as sunspots, high-altitude jet streams, barometric pressure, and the like; yet weather forecasts are always probabilistic because many of these variables change constantly, and the relationship between all of them is not fully known. The assumption underlying meteorology (weather prediction), however, is determinism. All sciences assume determinism.