Many of Locke's views were sharply criticized by rationalists and empiricists alike. In 1704, rationalist Gottfried Leibniz wrote a response to Locke's work in the form of a chapter-by-chapter rebuttal, titled the Nouveaux essais sur l'entendement humain (New Essays on Human Understanding). Leibniz was critical of a number of Locke's views in the Essay, including his rejection of innate ideas; his skepticism about species classification; and the possibility that matter might think, among other things. Leibniz thought that Locke's commitment to ideas of reflection in the Essay ultimately made him incapable of escaping the nativist position or being consistent in his empiricist doctrines of the mind's passivity.
Empiricist George Berkeley was equally critical of Locke's views in the Essay. Berkeley's most notable criticisms of Locke were first published in A Treatise Concerning the Principles of Human Knowledge, in which Berkeley holds that Locke's conception of abstract ideas are incoherent and lead to severe contradictions. He also argues that Locke's conception of material substance was unintelligible, a view which he also later advanced in the Three Dialogues Between Hylas and Philonous.
At the same time, Locke's work provided crucial groundwork for future empiricists such as David Hume. John Wynne published An Abridgment of Mr. Locke's Essay concerning the Human Understanding, with Locke's approval, in 1696. Likewise, Louisa Capper wrote An Abridgment of Locke's Essay concerning the Human Understanding, published in 1811.
Some European philosophers saw the book's impact on psychology as comparable to Isaac Newton's impact upon science. Voltaire wrote:[11]
Just as a skilled anatomist explains the workings of the human body, so does Locke's Essay on the Human Understanding give the natural history of consciousness.… So many philosophers having written the romance of the soul, a sage has arrived who has modestly written its history.
