force. Both these functions of punishment, the _medicinal_ and the
_deterrent_ function, are prospective. But there is asserted a third
function, which is retrospective: punishment is said to be
_retributive_. It is on this ground that the justification of eternal
punishment mainly rests. We are however here concerned, not with that
eternity, but in an endeavour to give a full and adequate view of
punishment in all its functions.

2. If punishment is never _retributive_, the human race in all
countries and ages has been the sport of a strange illusion. Everyone
knows what _vengeance_ means. It is a desire to punish some one, or to
see him punished, not prospectively and with an eye to the future, for
his improvement, or as a warning to others, but retrospectively and
looking to the past, that he may suffer for what he has done. Is then
the idea of vengeance nothing but an unclean phantom? Is there no such
thing as vengeance to a right-minded man? Then is there an evil
element, an element _essentially_ and _positively_ evil, in human
nature. No one will deny that the idea, and to some extent the desire,
of vengeance, of retaliation, of retrospective infliction of suffering
in retribution for evil done, of what we learn to call in the nursery
_tit for tat_, is natural to mankind. It is found in all men. We all
respond to the sentiment:

Mighty Fates, by Heaven's decree accomplish,
According as right passes from this side to that.
For hateful speech let speech of hate be paid back:
Justice exacting her due cries this aloud:
For murderous blow dealt let the murderer pay
By stroke of murder felt.
Do and it shall be done unto thee: