 Regarding the relationship between real essences and substance in general, Michael Ayers has argued that Locke uses the terms ‘substance’ and ‘real essence’ as extensionally equivalent, but not intensionally equivalent. That is, both terms refer to the same objects, but convey a very different meaning. For Ayers, Locke’s use of ‘substance’ conveys the idea of a thing that supports properties, whereas ‘real essence’ conveys the idea of a submicroscopic material structure that causes the powers of the object; these are different meanings, but both terms refer to only one  object.[6]