"I know it is an Opinion, that the Soul always thinks, and that it has the actual Perception of Ideas in it self constantly, as long as it exists; and that actual thinking is as inseparable from the Soul, as actual Extension is from the Body; which if true, to enquire after the beginning of a Man's Ideas, is the same, as to enquire after the beginning of his Soul."
— Locke, John (1632-1704)
I find over 25 entries in the ESTC (1690, 1694, 1695, 1700, 1706, 1710, 1715, 1721, 1726, 1731, 1735, 1741, 1748, 1753, 1759, 1760, 1765, 1768, 1775, 1777, 1786, 1788, 1793, 1795, 1796, 1798). See also the many abridgements issued in the period.
First published as An Essay Concerning Humane Understanding. In Four Books. (London: Printed by Eliz. Holt, for Thomas Basset, at the George in Fleetstreet, near St. Dunstan's Church, 1690). <Link to EEBO><EEBO-TCP>
Searching first in a Past Masters edition based on the 12th Edition of Locke's Works and proofread against the 1959 Fraser edition. More recent searches in EEBO-TCP.
Reading John Locke's An Essay Concerning Human Understanding, ed. Peter Nidditch (Oxford, Oxford UP, 1975)--against which I have checked the text searched in Past Masters. Note, Nidditch's text is based on 4th ed. of 1700.