91. In such a doctrine Locke, starting whence he did, could not remain at rest. We need not here repeat what has been said of it above in the consideration of his doctrine of substance. Taken strictly, it implies that ‘real existence’ consists in a permanent relation of ideas, said to be of secondary qualities, to each other in dependence on other ideas, said to be of primary qualities. In other words, in order to constitute reality, it takes ideas out of that particularity in time and place, which is yet pronounced the condition of reality, to give them an ‘abstract generality’ which is fictitious, and then treats them as constituents of a system of which the ‘invented’ relations of cause and effect and of identity are the framework. In short, it brings reality wholly within the region of thought, distinguishing it from the system of complex ideas or nominal essences which constitute our knowledge, not as the unknown opposite of all possible thought, but only as the complete from the incomplete. To one who logically carried out this view, the ground of distinction between fact and fancy would have to be found in the relation between thought as ‘objective,’ or in the world, and thought as so far communicated to us. Here, however, it could scarcely be found by Locke, with whom ‘thought’ meant simply a faculty of the ‘thinking thing,’ called a ‘soul,’ which might ride in a coach with him from Oxford to London. (Book II. chap, xxiii. sec. 20.) Was the distinction then to disappear altogether? Hence another view of real essence as unknown qualities of unknown body. 92. It is saved, though at the cost of abandoning the ‘new way of ideas,’ as it had been followed in the Second Book, by the transfer of real existence from the thing in which ideas are found, and whose qualities the complex of ideas in us, though inadequate, represents, to something called ‘body,’ necessarily unknown, because no ideas in us are in any way representative of it. To such an unknown body unknown qualities are supposed to belong under the designation ‘real essence.’ The subject of the nominal essence, just because its qualities, being matter of knowledge, are ideas in our minds, is a wholly different and a fictitious thing. How Locke mixes up these two meanings in ambiguity about body.