Sentence:  Now the progress of Knowledg being stopt by extreme Confidence on the one hand, and Diffidence on the other; I think that both are necessary, though perhaps one is more seasonable: For to believe that every thing is certain, is as great a <WSD>disinterest</WSD> to Science, as to conceive that nothing is so: 
Meaning of the word marked with <WSD> tags:  What is contrary to interest or advantage. (17th-19th c.)