 Science  Modern science is typically divided into three major branches wey consist of the natural sciences e.g., biology, chemistry, and physics, which study nature in the broadest sense; the social sciences e.g., economics, psychology, and sociology, which study individuals and societies; and the formal sciences e.g., logic, mathematics, and theoretical computer science, which study abstract concepts. There is disagreement, however, on whether the formal sciences actually constitute a science as they do not rely on empirical evidence. Disciplines wey use existing scientific knowledge for practical purposes, such as engineering and medicine, are described as applied sciences. 