THE WONDERS OF LIFE 



stniction of meteorological huts. The so-called "resur- 

 rection plants" {anastatica, the rose of Jericho, and 

 selaginella lepidophylla), which close up like a fist when 

 dry, spread their leaves out flat when moistened (the 

 leaves imbibing strongly on the inner side). There is 

 no more real case of "resuscitation" (as many believe) 

 in these cases than in the mythological resurrection of 

 the body. However, these phenomena of imbibition 

 are not active vital processes; they are independent of 

 the living plasm, and due solely to the physical constitu- 

 tion of the dead cell-membranes. 



In contrast with these passive movements of organ- 

 isms, we have the active movements which proceed from 

 the living plasm. In the ultimate analysis, it is true, 

 these may be reduced to the action of physical laws just 

 as well as the passive movements. But the causes of 

 them are not so clear and obvious; they are connected 

 with the complicated chemical molecular processes of the 

 living plasm, of the physical regularity of which we are 

 now fully convinced, though their complicated mech- 

 anism is not yet understood. We may divide into two 

 groups the many different movements, which are called 

 vital in this stricter sense, and were formerly regarded 

 as evidences of the presence of a mystic vital force, 

 according as the stimulus — the sensation of which is 

 caused by the movement — is directly perceptible or not. 

 In the first case, we have stimulated (or reflex or para- 

 tonic) movements, and in the second voluntary (auton- 

 omous or spontaneous) movements. As the will ap- 

 pears to be free in the latter, they have been left out 

 of consideration by many physiologists, and handed over 

 to the treatment of the metaphysical psychologist. On 

 our monistic principles this is a grave error; nor is it 

 improved when " psychonomism " appeals to a false 

 theory of knowledge. On the contrary, the conscious 

 will (and conscious sensation) is itself a physical and 



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