 …if the powers of a System of Matter may intirely cease upon the least Alteration of a Part of that System, it is evident that the Powers of the System inhere not in the Parts in the same Sense with Magnitude and Motion: for divide and vary the Parts of Matter as much as you will, there will be Magnitude and may be Motion; but divide or vary the least Part of the Eye, and the Power of contributing to the Act of Vision is intirely at an end. (Clarke 1738 [1928: 768]; Clarke and Collins 2011: 72)