The riddle of the Sphinx

When asked, “What is the creature that walks on four legs in the morning, two legs at noon and three in the evening?” Oedipus correctly answers, “Man.”

The mythological Sphinx’s riddle illustrates the physical progress of Man through life in a linear fashion: as a baby, Man walks on all fours; as an adult on two feet; and when elderly with three appendages through the use of a cane.

As I pack two folding canes, not used in almost three years, into my backpack, it strikes me that our trek thro...