text: For example, the matter of a house is the bricks, stones, timbers, etc., or whatever constitutes the potential house, while the form of the substance is the actual house, namely 'covering for bodies and chattels' or any other differentia that let us define something as a house.The formula that gives the components is the account of the matter, and the formula that gives the differentia is the account of the form.Immanent realism Like his teacher Plato, Aristotle's philosophy aims at the universal.Aristotle's ontology places the universal (katholou) in particulars (kath' hekaston), things in the world, whereas for Plato the universal is a separately existing form which actual things imitate.For Aristotle, "form" is still what phenomena are based on, but is "instantiated" in a particular substance.Plato argued that all things have a universal form, which could be either a property or a relation to other things.When one looks at an apple, for example, one sees an apple, and one can also analyse a form of an apple.In this distinction, there is a particular apple and a universal form of an apple.Moreover, one can place an apple next to a book, so that one can speak of both the book and apple as being next to each other.Plato argued that there are some universal forms that are not a part of particular things.For example, it is possible that there is no particular good in existence, but "good" is still a proper universal form.Aristotle disagreed with Plato on this point, arguing that all universals are instantiated at some period of time, and that there are no universals that are unattached to existing things.In addition, Aristotle disagreed with Plato about the location of universals.Where Plato spoke of the forms as existing separately from the things that participate in them, Aristotle maintained that universals exist within each thing on which each universal is predicated.