NEW CONCEPTIONS IN SCIENCE 



action of your hands or of the glowing melody they 

 thus mechanically produce. 



But between this astonishing achievement and 

 the beginning there have been countless hours 

 where every crook of a finger and every twisty 

 note was a matter of the most laborious conscious- 

 ness. This we call thought. In terms of brain 

 physiology, it was the stimulation of a wide area 

 of brain-cells, either by nerve currents from other 

 cells of the brain or from without the brain, as, 

 for example, from the retina. Whatever thought, 

 or consciousness, may be in itself, it seems probable 

 that its physical basis is the stimulation of a rela- 

 tively wide area of the brain that is to say, the 

 simultaneous activity of a large number of brain- 

 cells. In this view, the action becomes unconscious 

 when the area or number is lessened. 



This stimulation of a wide area can be effected 

 only by means of nerve connections between the 

 different cells. These connections are known as 

 association fibres, and are perfectly discernible by 

 the microscope. Their number is immense. Many 

 cells have scores and even hundreds, and, as the 

 cells are numbered by hundreds of millions, it is 

 easy to see that they reach to an unthinkable sum. 



It is by means of these association fibres that 

 we have what is called association of ideas. Clever 

 people evidently are well provided with association 



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