Whether the five exterior senses are properly distinguished?

Objections

Objection 1 : It would seem inaccurate to distinguish five exterior senses. But there are many kinds of accidents. Therefore, as powers are distinguished by their objects, it seems that the senses are multiplied according to the number of the kinds of accidents.
Objection 2 : Further, magnitude and shape, and other things which are called "common sensibles," are "not sensibles by accident," but are contradistinguished from them by the Philosopher (De Anima ii, 6). Now the diversity of objects, as such, diversifies the powers. Since, therefore, magnitude and shape are further from color than sound is, it seems that there is much more need for another sensitive power than can grasp magnitude or shape than for that which grasps color or sound.
Objection 3 : Further, one sense regards one contrariety; as sight regards white and black. But the sense of touch grasps several contraries; such as hot or cold, damp or dry, and suchlike. Therefore it is not a single sense but several. Therefore there are more than five senses.
Objection 4 : Further, a species is not divided against its genus. But taste is a kind of touch. Therefore it should not be classed as a distinct sense of touch.