392 NEW ESSAYS 



for we experiment in ourselves thinking. The idea of 

 this action or mode of thinking is inconsistent with the 

 idea of self-subsistence, and therefore has a necessary con- 

 nexion with a support or subject of inhesion : the idea 

 of that support is what we call substance. . . . For the 

 general idea of substance being the same everytvhere 14 , the 

 modification of thinking, or the power of thinking joined 

 to it, makes it a spirit, without considering what other 

 modification it has, as whether it has the modification of 

 solidity or no. As on the other side, substance that has 

 the modification of solidity is matter, whether it has 

 the modification of thinking or no. And therefore if 

 your lordship means by a spiritual an immaterial sub- 

 stance, I grant I have not proved, nor upon my prin- 

 ciples can it be proved (your lordship meaning, as I think 

 you do, demonstratively proved) that there is an imma- 

 terial substance in us that thinks. Though I presume, 

 from what I have said about the supposition of a system 

 of matter thinking (bk. iv. ch. 10, 16) (which there de- 

 monstrates that God is fmmaterial), it will prove in the 

 highest degree probable that the thinking substance in 

 us is immaterial. . . . Yet I have shown ' (adds the author, 

 p. 68) U1 ' that all the great ends of religion and morality 

 are secured barely by the immortality of the soul, without 

 a necessary supposition that the soul is immaterial.' 



The learned Bishop in his reply to this letter, in order 

 to show that our author was of another opinion when 

 he wrote the second book of the Essay, quotes from it 

 (p. 5i) 142 the passage (taken from the same book, ch. 23, 

 1 5), in which it is said that l by the simple ideas we 

 have taken from our own minds 143 we are able to frame 



140 Leibniz's italics. l41 Ed. 1823, vol. iv. p. 34. 



142 Stillingfleet's Works, vol. iii. p. 534. 



143 Leibniz's translation has ' from the operations of our mind.' 

 I give the words as they are in Stillingfleet, who condenses Locke's 

 sentence, which is as follows : ' By the simple ideas we have taken 



\ iprfrom those operations of our own minds, which we experiment 

 .daily in ourselves, as thinking, understanding, willing, knowing. 



