in every instance of change or being acted upon, the thing undergoing change must first undergo locomotion.”

Abū al-Barakāt said:

“This is impossible, for souls acquire new cognitions and knowledge without moving from place to place, according to his own view. He does not believe that they occupy any place at all, so how could they move within it? This occurs only in bodies, and only in certain bodies and under certain conditions, as with heating and cooling. Nor does it invariably occur even in them: a large stone grows hot without rising and grows cold without descending. Indeed, it does not even move from its place. This occurs only with those particles of water that rise as vapor and those dust-like particles of earth that rise as smoke—not with other bodies, such as large, solid stones, which become hot enough to burn while remaining motionless in their place.

Water becomes very hot while remaining in place without evaporating; only some of its particles evaporate. Locomotion thus follows alteration, rather than preceding it as he maintained when he said:

‘All these are motions that occur later, after locomotion.’