ON THE PHYSICAL BASIS OF LIFE ^ 

 [1868] 



In order to make the title of this discourse generally intel- 

 ligible, I have translated the term "Protoplasm," which is 

 the scientific name of the substance of which I am about to 

 speak, by the words "the physical basis of life." I suppose 

 that, to many, the idea that there is such a thing as a physical 

 basis, or matter, of life may be novel — so widely spread is 

 the conception of life as a something which works through 

 matter, but is independent of it; and even those who are 

 aware that matter and life are inseparably connected, may 

 not be prepared for the conclusion plainly suggested by the 

 phrase, ^^the physical basis or matter of life," that there is 

 some one kind of matter which is common to all living 

 beings, and that their endless diversities are bound together 

 by a physical, as well as an ideal, unity. In fact, when first 

 apprehended, such a doctrine as this appears almost shock- 

 ing to common sense. 



1 The substance of this paper was contained in a discourse which 

 was delivered in Edinburgh on the evening of Sunday, the 8th of No- 

 vember, 1868 — being the first of a series of Sunday evening addresses 

 upon non- theological topics, instituted by the Rev. J. Cranbrook. 

 Some phrases, which could possess only a transitory and local interest, 

 have been omilted; instead of the newspaper report of the Archbishop 

 of York's address, his Grace's subsequently published pamphlet On 

 the Limits of Philosophical Inquiry is quoted; and I have, here and 

 there, endeavoured to express my meaning more fully and clearly than 

 I seem to have done in speaking — if I may judge by sundry criticisms 

 upon what I am supposed to have said, which have appeared. But 

 in substance, and, so far as my recollection serves, in form, what is 

 here written corresponds with what was there said. 



