Hossein Jorjani
First publication: 2026 – 06 – 30
Bacon’s use of notio (“notion”) retained the Aristotelian conception of a form in the soul or intellect (μορφή ἐν τῇ ψυχῇ), yet fundamentally transformed its epistemological function. In Aristotelian psychology and logic, a notion denoted the intellect’s grasp of the universal—an abstraction derived from sense perception and serving as the middle term of reasoning. Such notiones were regarded as stable, valid reflections of reality. Bacon adopted the term but rejected this presumption of adequacy. For him, the notiones communes (“common notions”) by which human beings habitually think were not trustworthy universals but confused residues of sensory experience, deformed by the idola mentis (“idols of the mind”). Hence his reform of knowledge began with the critique and reconstruction of notions through inductio vera (“true induction”).
In this respect, Bacon’s notion occupies a position midway between Aristotle’s koinē ennoia (“common concept”) and the modern scientific concept understood as a methodologically revisable construct: it is both the mental unit of thought and the object of methodological correction. Whereas Aristotle regarded the formation of notions as a natural process of abstraction, Bacon made their purification a conscious methodological task.
Hossein Jorjani 