112. Mathematical ideas, though ideas of ‘primary qualities of body,’ have ‘barely an ideal existence’.
113. Summary view of Locke’s difficulties in regard to the real.
114. Why they do not trouble him more.
115. They re-appear in his doctrine of propositions.
116. The knowledge expressed by a proposition, though certain, may not be real …
117. … when the knowledge concerns substances. In this case general truth must be merely verbal. Mathematical truths, since they concern not substances, may be both general and real.
118. Significance of this doctrine.
119. Fatal to the notion that mathematical truths, though general, are got from experience:
120. … and to received views of natural science: but Locke not so clear about this.
121. Ambiguity as to real essence causes like ambiguity as to science of nature. Particular experiment cannot afford general knowledge.