'Our condition, both public and private, is full of imperfections;
yet there is nothing useless in Nature, not even uselessness
itself.... Our being is cemented with sickly qualities: ambition,
jealousy, envy, vengeance, superstition, despair dwell in us, and
hold there so natural a possession that their counterfeit is also
recognised in beasts; for instance, cruelty--so unnatural a vice.
Yet he who would root out the seed of these qualities from the human
breast would destroy the fundamental conditions of our life.'

Now, Hamlet's resolution to be 'cruel, but not unnatural,' is but a
fresh satire against Montaigne's train of thoughts, who would fain be
a Humanist, but who does not break with the reasoning of Loyola and
of the Church, by which he permits himself to be guided as by
the competent authority, and which tolerates cruelty--nay, orders its
being employed for the furtherance of what it calls the 'good aim.'

The idea that cruelty is a necessary but useful evil, no doubt
induced Montaigne [42] to declare that to kill a man from a feeling
of revenge is tantamount to our protecting him, for we thus 'withdraw
him from our attacks.' Furthermore, this Humanist argues that revenge
is to be regretted if its object does not feel its intention; for,
even as he who takes revenge intends to derive pleasure from
it, so he upon whom revenge is taken must perceive that intention,
in order to be harrowed with feelings of pain and repentance. 'To kill
him, is to render further attacks against him impossible; not to
revenge what he has done.'

Shakspere already gives Hamlet an opportunity in the following scene
to prove to us that there is no boundary between cruel and unnatural