Behind the mask of indifference is bottomless misery and behind apparent callousness, despair.
John BowlbyThus, just as animals of many species, including man, are disposed to respond with fear to sudden movement or a marked change in level of sound or light because to do so has a survival value, so are many species, including man, disposed to respond to separation from a potentially caregiving figure and for the same reasons.
John Bowlby