Balancing Opposites -- Tagore's Epigrams

Many important mathematical ideas occur as pairs of opposites:
         -2 and +2 (additive inverses), 5 and 1/5 (multiplicative inverses),  
         bounded and unbounded, rational and irrational, 
         convergent and divergent, finite and infinite
Some other familiar mathematical notions occur often in contrasting pairs but are not fully opposites:
         horizontal and vertical, positive and negative, 
         open and closed, perpendicular and parallel

Recently I have returned to reading work by Rabindranath Tagore (1861-1931; Bengal, India;  winner of the 1913 Nobel Prize in Literature) and I enjoy reflecting on contrasts posed by this reflective poet in a series of "Epigrams":

Epigrams      by Rabindranath Tagore

I will close my door to shut out all possible errors.
"But how am I to enter in?" cried Truth.