Prompt for First Classical Argument

Consider the distinct perspectives expressed in the following statements. 

If you develop the absolute sense of certainty that powerful beliefs provide, then you can get yourself to accomplish virtually anything, including those things that other people are certain are impossible. 
--William Lyon Phelps, American educator, journalist, and professor (1865–1943) 

I think we ought always to entertain our opinions with some measure of doubt. I shouldn’t wish people dogmatically to believe any philosophy, not even mine. 
--Bertrand Russell, British author, mathematician, and philosopher (1872–1970) 

In a well-organized essay, take a position on the relationship between certainty and doubt. Support your argument with appropriate evidence and examples.