Philosophers        
    
    
                        
            
  
      
  
                I seem to remember there was a medieval philosopher--maybe Russell mentions him in his History of Western Philosophy--who talked about peer influence or what a social scientist today might call regression toward the mean.  He advised that, to live a saintly life, one should surround oneself with saintly people.  Who was he? Did he write anything available today?  Any pithy quotes?        
Accepted:August 14, 2015          
                  
    
  
  
  
      Accepted:
August 14, 2015
