Harris agrees with the 19th-century view that laws are abstractions from empirical evidence: "...sociocultural entities are constructed from the direct or indirect observation of the behavior and thought of specific individuals ..." Institutions are not a physical reality; only people are. When they act in society, they do so according to the laws of history, of which they are not aware; hence, there is no historical element of free will. Like the 20th-century anthropologists in general, Harris places a high value on the empiricism, or collection of data. This function must be performed by trained observers.