"[M]ental Abstraction... is not [only the] Property of Mathematics, but is common to all Sciences. For every Science considers the Nature of its own Subject abstracted from all others; forms its own general Precepts and Theorems; and separates its own Properties from the Properties of others... For example, Physics considers the constitutive Principles, Matter, Form, &c. of Body in general; then the Affections common to all Bodies, viz. Quantity, Place, Motion, Rest, and the like; from whence it descends to the next lower Species, investigating their particular Natures and Properties; but meddles not with particular Bodies or Individuals, as well because they are innumerable and distinguished from one another by innumerable Differences... The same way Geometry proposes Magnitude for the Subject of its Enquiry, not the peculiar Magnitude of this or that Body, but the Magnitude taken universally; together with its general Affections, viz. Divisibility, Congruence, Proportionality, a Capacity of different Situation and Position, Mobility &c. declaring these to be inherent to it, and after what manner they are so: Next it defines the various Species of Magnitude, (viz. a Line, Superficies, and a Body or Solid) and particularly draws forth and demonstrates their distinct Properties; continually dividing these Species into others more contract, and searching and proving their Affections by universal Propositions, Rules and Theorems lawfully demonstrated, till it has wholly exhausted its Subject, and descended to the very lowest Species. And these Theorems however more or less general as to their Matter, may be truly and properly accommodated to Subjects particular to themselves. True Mathematical Abstraction then, is such as agrees with all other Sciences and Disciplines, nothing else being meant (whatsoever some do strangely say of it) than an Abstraction from particular Subjects, or a distinct Consideration of certain things more universal, others less universal being ommitted and as it were neglected."