THE VITAL ORDER 



ical processes in the brain and the nervous system; 

 but is that their final explanation? The sunlight 

 has little effect on a withered leaf, but see what 

 effect it has upon the green leaf upon the tree ! The 

 sunlight is the same, but it falls upon a new force 

 or potency in the chlorophyll of the leaf, a bit 

 of chemistry there inspired by life, and the heat 

 of the sun is stored up in the carbon or woody tis- 

 sues of the plant or tree, to be given out again in 

 our stoves or fireplaces. And behold how much 

 more of the solar heat is stored up in one kind of a 

 tree than in certain other kinds, how much in the 

 hickory, oak, maple, and how little comparatively 

 in the pine, spruce, linden, all through the magic 

 of something in the leaf, or shall we say of the 

 spirit of the tree? If the laws of matter and force 

 alone account for the living organism, if we do not 

 have to think of something that organizes, then 

 how do we account for the marvelous diversity of 

 living forms, and their still more marvelous power 

 of adaptation to changed conditions, since the laws 

 of matter and force are the same everywhere? 

 Science can deal only with the mechanism and 

 chemistry of life, not with its essence; that which 

 sets up the new activity in matter that we call 

 vital is beyond its analysis. It is hard to believe 

 that we have told the whole truth about a liv- 

 ing body when we have enumerated all its chem- 

 ical and mechanical activities. It is by such enu- 

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