Some Grooks by Piet Hein

Problems worthy 
of attack 
prove their worth 
by hitting back. 

Put up in a place 
where it's easy to see 
the cryptic admonishment 
When you feel how depressingly 
slowly you climb, 
it's well to remember that 
      Things Take Time. 

The road to wisdom? - Well, it's plain 
and simple to express: 
   and err 
   and err again 
   but less 
   and less 
   and less. 

Those who always
know what’s best
a universal pest

He that lets
the small things bind him
leaves the great
undone behind him.