222 THE CASE AGAINST EVOLUTION 



The nature of conceptual thought is such as to exclude the 

 participation of matter as a constituent of its specific agent 

 and receptive subject. The objects of a cerebral sense like 

 the imagination are endowed with extension, color, shape, 

 volume, mass, temperature, and other physical properties, in 

 virtue of which they can set up vibrations in an extended 

 medium or modify an extended organ by immediate physical 

 contact. But, while imagination makes us conscious of ob- 

 jects capable of stimulating extended material organs, the 

 objects, of which we are conscious in abstract thinking, are 

 divested of all the sensible properties, extension, and spe- 

 cific energies, which would enable them to modify a material 

 neuron, or produce a physical impression upon a material 

 receptor of any kind whatever. Between an extended ma- 

 terial receptor, like a sense-organ or a cerebral neuron, and 

 the nondimensional, dematerialized object or content of an ab- 

 stract thought, like science, heroism, or morality, there is no 

 conceivable proportion. How can a material organ be af- 

 fected by what is supersensible, unextended, imponderable, 

 invisible, intangible, and uncircumscribed by the limitations 

 of space and time? Extended receptors are necessary for 

 picking up the vibrations of a tridimensional medium (like 

 air or ether), and they are, likewise, essential for the recep- 

 tion of impressions produced by surface-contact with an ex- 

 terior corporeal mass. In short, sensory neurons are needed 

 to receive and transmit inward the quantitative and measur- 

 able excitations of the material stimuli of the external world, 

 and central neurons are required as tablets upon which these 

 incoming excitations may imprint extended neurograms, that 

 are proportionate in intensity and extensity to the external 

 stimulus apprehended, and that underlie and determine the 

 concrete imagery (of which they are the physical basis). But 

 when it comes to perceiving and representing the meaning 

 of duty, truth, error, cause, effect, psychology, means, end, 

 entity, logarithms, etc., our mind can derive no benefit from 

 the cooperation of a material organ. In such thinking we 



