But if I go further and seek among these 
     characteristics the principal one, which includes almost all 
     the rest, I discover that in most of the operations of the 
     mind each American appeals only to the individual effort 
     of his own understanding.
          America is therefore one of the countries where the 
     precepts of Descartes are least studied and are best 
     applied. . . . Everyone shuts himself tightly up within 
     himself and insists upon judging the world from there. (5)

His skill in creating interplay between the written and oral 
modes of perceptual structure enabled de Tocqueville to 
achieve “scientific” insights into psychology and politics. By this 
interplay of two modes of perception he achieved prophetic 
understanding while other observers were merely expressing 
their private viewpoints. De Tocqueville knew well that