There is a long-standing fascination with those who can accomplish astounding feats of mental agility.

BBC: How does a human calculator do it?

On a deeper level mental agility is the capacity to weigh conflicting options, to be able to make hard choices when both options are good, such as which business to buy or which employee to promote.

FORBES: Three Traits Every Great Leader Must Demonstrate

Spontaneity really comes down to mental agility.

FORBES: Three Traits Every Great Leader Must Demonstrate