386 



ON HUMAN UNDERSTANDING. 



external senses. This insubstantial image or picture, in order to distiii- 

 guish it from the intellectual pattern or idea of Plato, he denominated a 

 phantasm. And as he supported with Plato the existence of an intelligible 

 as well as of a sensible world, it was another part of his hypothesis that, 

 while things sensible are perceived by sensible phantasms, things intelli- 

 gible are perceived by intelligible phantasms ; and consequently that virtue 

 and vice, truth and falsehood, time, space and numbers, have all their pic- 

 tures and phantasms, as well as plants, houses, and animals. 



Epicurus admitted a part of this hypothesis, and taught it contempora- 

 neously at Mitylene, but the greater part he openly opposed and ridiculed. 

 He concurred in the doctrine that the mind perceives sensible objects by 

 means of sensible images ; but he contended that those images are as 

 strictly material as the objects from which they emanate ; and that, if we 

 allow them to possess material qualities, we must necessarily allow them 

 at the same time to possess the substance to which such qualities appertain. 

 Epicurus, therefore, believed the perceptions of the mind to be real and 

 substantial effigies, and to these effigies he gave the name of £<^<yA<», (idola) 

 or SPECIES, in contradistinction to the insubstantial phantasms of Aristotle, 

 and the intellectual or formative ideas of Plato. He maintained that all 

 external objects are perpetually throwing off fine alternate waves of dif- 

 ferent flavours, odours, colours, shapes, and other qualities ; which, by 

 striking against their appropriate senses, excite in the senses themselves a 

 perception of the qualities and presence of the parent object : and are 

 immediately conveyed by the sentient channel to the chamber of the mind, 

 or sensory, without any injury to their texture : in the same manner as 

 heat, light, and magnetism pervade solid substances, and still retain their 

 integrity. And he affirmed further that, instead of the existence of an 

 imaginary, intelligible world, throwing off intelligible images, it is from 

 the sensible or material world alone that the mind, by the exercise of its 

 proper faculties, in union with that of the corporeal senses, derives every 

 branch of knowledge, physical, moral, or mathematical. 



If this view of the abstruse subject before us be correct, as I flatter 

 myself it is, I may recapitulate in few words, that the external perceptions 

 of the mind are, according to Plato, the primitive or mtellectual patterns 

 from which the forms and other qualities of objects have been taken ; ac- 

 cording to Aristotle, insubstantial pictures of them, as though reflected 

 from a mirror ; and, according to Epicurus, substantial or material effi- 

 gies : such perceptions being under the first view of them denominated 

 IDEAS ; under the second, phantasms ; under the third, idola, or 



SPECIES. 



While such were the fixed and promulgated tenets of Plato, Aristotle, 

 and Epicurus, there were other philosophers of Greece, or who at least 

 have been so denominated, that openly professed themselves to be without 

 tenets of any kind ; who declared that nothing was known or could be 

 known upon any subject ; and who, consequently, inculcated an universal 

 skepticism. Of this delirious class of disputants, who were suffered to 

 wander at large without a strait waistcoat, there are two that are pre- 

 eminently entitled to our attention, Pyrrho and Arcesilas. Pyrrho studied 

 first in the atomic school of Democritus, and seems to have lost his senses 

 upon the question of the infinite divisibility of matter, a question which 

 has not unfrequently given birth to the same disease in modern times. 

 He first doubted the solidity of its elementary atoms, — he next found out, 

 that if these be not solid, every thing slips away from the fingers in a mo 



