Scotistic realism

Scotist realism, sometimes called Scotist formalism, is the Scotist position on the problem of universals. This position emerged as a response to what was called the "problem of universals", which was an ancient problem in metaphysics about whether universals exist. For John Duns Scotus, a Franciscan philosopher, theologian and Catholic priest, universals such as "greenness" and "goodness" exist in reality. This is opposed to the later conceptualism of William of Ockham, and the earlier views of Abelard and others, which say universals exist only within the mind and have no external or substantial reality.

The problem of universals existed as early as Plato, who taught the Theory of Forms, that universal "forms" existed. This opinion was rejected by many later thinkers, such as Peter Abelard - who instead argued that forms are merely mental constructs.

Scotus denied these claims; in his Opus Oxoniense he argued that universals have a real and substantial existence. For Scotus, the problem of universals was closely tied to that of individuation, by identifying what makes a particular thing this or that particular thing; we could also come to understand if any form of universal exists, it is in this work that Scotus introduces the word "haecceity", which means the "thisness" of a particular object – what makes it what it is.

I say then that the main reason for the likening or similarity is the form itself shared between the generator and the generated, not according to individual unity and identity insofar as it is "this" form, but according to a lesser unity and identity insofar as it is a form. The reason for generating is in accordance with this. Form also is a more principal reason for the distinction than matter is, because just as the form is more principally that by which something is a composite than the matter is, so it is more principally that by which a composite is one, and consequently not distinguished in itself and yet distinct from everything else

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