Sentence:  That is to say, it is the Analogue of Space, not in the sense in which we formerly regarded Space as the "negation"<!--italics in original--> of Matter; but in the sense of "Infinite <WSD>Dimensionality</WSD>"<!--itals in orig-->, or of <WSD>Dimensionality</WSD> in all directions, as a vague generalization from the three spatial dimensions "Length", "Breadth", and "Thickness".<!--and again--> 
Meaning of the word marked with <WSD> tags:  The number of dimensions something has.