學 而 不 思 則 罔 思 而 不 學 則 殆

學而不思則罔，思而不學則殆

学而不思则罔，思而不学则殆

xue2 er2 bu4 si1 ze2 wang3 , si1 er2 bu4 xue2 ze2 dai4

To learn without thinking is blindness, to think without learning is idleness (Confucius). Learning without reasoning leads to confusion, thinking without learning is wasted effort.