Baconian method, methodical observation of facts as a means of studying and interpreting natural phenomena. This essentially empirical method was formulated early in the 17th century by Francis Bacon, an English philosopher, as a scientific substitute for the prevailing systems of thought, which, to his mind, relied all to often on fanciful guessing and the mere citing of authorities to establish truths of science. After first dismissing all prejudices and preconceptions, Bacon’s method, as explained in Novum Organum (1620; “New Instrument”), consisted of three main steps: first, a description of facts; second, a tabulation, or classification, of those facts into three categories—instances of the presence of the characteristic under investigation, instances of its absence, or instances of its presence in varying degrees; third, the rejection of whatever appears, in the light of these tables, not to be connected with the phenomenon under investigation and the determination of what is connected with it.

Bacon may be credited with recognizing, in their essence, the method of agreement, the joint method, and the method of concomitant variations. His emphasis on the exhaustive cataloguing of facts, however, has since been replaced as a scientific method, for it provided no means of bringing investigation to an end or of insightful delimitation of the problem by creative use of hypotheses.