SOURCES OF SCIENTIFIC BELIEFS. 91. 



idea, more or less fixed in the mind, and capable of being 

 expressed in a proposition or statement ; and the act of 

 belief is a conscious mental perception of such an idea. 



The sources of our beliefs are the same as those of our 

 ideas, viz. experience, including what has been instilled 

 into us as well as what we have been told and have read, 

 or have had otherwise impressed upon us, together with 

 our generalisations, conclusions, and inferences from the 

 whole of these. Many of the ideas which we obtain by either 

 one or other of these means, we more or less believe until we 

 either meet with what appears to us to be opposing evidence 

 or with new ideas which more accord with our feelings. 



Our beliefs vary in kind with our ideas ; thus they 

 may be either primary or axiomatic, true or false, intelli- 

 gent or blind, latent or present, strong or feeble, distinct 

 or vague, &c. A great proportion of human beliefs, espe- 

 cially in concrete subjects, consists of hypotheses. Beliefs 

 may possess every degree of firmness, depending upon the 

 fixity of the ideas ; and the more fixed the ideas, the more 

 firm the beliefs. A very firm blind belief produces ignorant 

 obstinacy. The strength or weakness, distinctness or 

 indistinctness of our beliefs also corresponds and varies 

 with that of the particular ideas. Nearly all our beliefs 

 are latent in the memory. 



Among our primary or axiomatic beliefs are usually 

 included : 



1 . That of our present existence. 



2. Of our past existence and personal identity. 



3. Of the external and independent existence of nature. 



4. Of the existence of an efficient cause for all things. 



5. The existence of uniformity of cause and effect. 



6. Also various logical and mathematical axioms. 



Our minds yield to repeated impressions, especially in 



