"And by this means, we may, perhaps, attain a new microscope or species of optics, by which, in the moral sciences, the most minute, and most simple ideas may be so enlarged as to fall readily under our apprehension, and be equally known with the grossest and most sensible ideas, that can be the object of our enquiry."
— Hume, David (1711-1776)
First published as Philosophical Essays Concerning Human Understanding (London: Printed for A Millar, 1748). <Link to ECCO><Link to ECCO-TCP><Link to 1748 edition in Google Books> "Second edition" in 1750, "third edition" in 1756. First titled An Enquiry Concerning Human Understanding in 1758.
In ECCO-TCP, see also Essays and Treatises: on Several Subjects. By David Hume, Esq, 4 vols. (London: Printed for A. Millar; and A. Kincaid and A. Donaldson, at Edinburgh, 1760). <Link to vol. III>
Text from David Hume, Enquiries Concerning Human Understanding and Concerning the Principles of Morals. 3rd edition. Ed. L. A. Selby-Bigge; P. H. Nidditch (Oxford: Oxford University Press, 1975). Note, Nidditch reproduces the the second volume of the posthumous edition of 1777, which he has collated with the preceding 1772 edition.