FRANCIS BACON. 133 



by Bacon, among the idols of the tribe. The imperfection of our senses 

 and means of observation he names as another cause of error. 



The idols of the cave (idola speeds) are those prejudices which are 

 peculiar to each individual mind. " For, in addition to the general 

 waywardness of human nature, every man has his own peculiar den or 

 cavern, which breaks or corrupts the light of nature, either on account 

 of his constitution and disposition of mind, his education and the 

 society he keeps, his course of reading and the authorities he most re- 

 spects, his peculiar impressions, as made on a mind that is pre-occu- 

 pied and prepossessed, or is in a calm and unbiassed frame ; so that 

 the human spirit, as it is differently disposed in different individuals, 

 is a thing fluctuating, disorderly, and almost accidental." Speaking 

 elsewhere of this class of prejudices, Bacon adopts his former meta- 

 phor, and compares each mind to " a glass with its surface differently 

 cut, so as differently to receive, reflect, and refract the rays of light that 

 fall upon it." Some minds, he remarks, are quick at perceiving the 

 differences of things, others catch the similarities ; each of these ten- 

 dencies may run into excess. The particular studies, also, to which a 

 man is devoted, may warp his judgment in other pursuits. 



The third class of prejudices are denominated the idols of the market- 

 place (idola fort), and under this title Bacon ranges the errors that arise 

 in the use of language as the means of intercourse between men. He 

 pronounces this class of prejudices the most troublesome of all. Words 

 are, for the most part, accommodated to the notions of the common 

 people, and they define things only by those particulars that are most 

 obvious to ordinary understandings. Perhaps no form of error has been 

 and is more persistent than the tendency to suppose that whatever has 

 a name has a separate and distinct existence. Such words as fate, 

 chance, fortune, nature, etc., are not the names of real beings, as the 

 reader will perceive on reflection. Time is another word which is very 

 commonly but wrongly supposed to indicate some real thing, whereas 

 it implies merely a relation. 



The idols of the theatre (idola theatri) are the illusions which arise 

 from the various systems of philosophy, which Bacon compares to so 

 many stage plays, exhibiting nothing but fictitious and theatrical worlds; 

 and there may, he says, still be invented many other fables of this kind. 

 The idols of this class do not naturally possess men's minds, but are 

 therein set up by their own labour and study. Bacon divides these 

 visionary systems of philosophy into three kinds the sophistical, the 

 empirical, and the superstitious. The sophistical philosophies are those 

 which are founded on a few hasty observations, the inventor supplying 

 the greater part of the system from his own mind : the physical theories 

 of Aristotle are of this kind. The empirical systems may repose on 

 well-ordered experiments, but their speculations are carried far beyond 

 the range warranted by the ascertained facts : thus, the older chemists 

 founded on a very few simple experiments vast speculative systems 



