Document Type : Research Paper
On the basis of substantial motion the whole material world and nature are under constant change. The question might be raised, accordingly, whether one can obtain knowledge of any material being. That is to say, if the very substance of any given material thing and in consequence its accidents are entirely in constant motion, nothing of them can be the object of knowledge, since as soon as an external thing is perceived by perceiver's faculty of knowledge, it will, strictly speaking, disappear and something new will come into being. As a result, nothing, from animals to minerals whatsoever, remains the same so as to make it possible to become object of knowledge. Of any given object of our perception, indeed, we can speak of not one fact but many indivisible facts. Knowledge itself is thus not one and the same but something changeable, discontinuous and instable.
In response to this crucial question, it is obvious that one should consider other positions taken by Mulla Sadra, agreat Muslim philosopher, regarding motion, substantial motion, reality of knowledge, as well as his understanding of existence in general so that he can receive consistent answers to the question raised.