The question that “Why does magnet attract?” always played the role of testing criteria for explanatory sufficiency of theories of nature which depend on sensible qualities. The reason for this is that the attraction of magnet has become the paradigmatic example of the special properties (idiotês - khawass), which are characterized as unexplainable, unknowable and strange because of their irreducibility to basic sensible qualities. While peripatetic and Galenic theories of
nature cannot give any sufficient and coherent explanation for these properties, Alchemic tradition and particularist model of physical theories of the ancient and Islamic periods offer various explanations for them. Differing from these all,
Avicenna criticized alchemic and particularist explanations and found a new way for explaining the magnetic attraction and the special properties in the explanatory framework of physical theories. This new way of explanation consists of dispensing with the theories which depend on sensible qualities and adopting a theory which depend on intelligible forms. The latter has two components which can be called as the theories of “the two excesses” and “the two meanings”.
Until the emergence of the new natural philosophies in the seventeenth century, this new physical theory provided the explanatory sufficiency and legitimacy of nature-centered qualitative model. The first excess of the theory of “the two excesses” is physical and corresponds to natural dispositions arising from the elemental complexions, and the second excess is metaphysical and corresponds to divine effulgence transforming the dispositions into manifest reality through
actualizing them. The first meaning of the theory of “the two meanings” is physical and corresponds to observable forms of natural substances and its second meaning is metaphysical and corresponds to the unobservable intelligible forms
which play the role of metaphysical ground of observables. The distinction between sensible and intelligible meanings aims to explain all sensible properties with intelligible forms and play a central role in natural sciences, just like the role
the distinction of essence and existence play in metaphysics. This article first describes the ways of rationalizations of special properties and magnetic attraction in the particularist and continuist physical theories. Then, it discusses how Avicenna’s new model of explanation naturalizes these special properties and how it supplants the nature-centered physical theories which depend on sensible qualities.