A central concept in science and the scientific method is that all evidence must be empirical, or empirically based, that is, dependent on evidence or consequences that are observable by the senses. Empirical data is data that's produced by experiment or observation. It is usually differentiated from the philosophic usage of empiricism by the use of the adjective "empirical" or the adverb "empirically." "Empirical" as an adjective or adverb is used in conjunction with both the natural and social… (More on Empirical)