What I must do is all that concerns me, not what the people think. This rule, equally arduous in actual and in intellectual life, may serve for the whole distinction between greatness and meanness.
He alone is worthy of the appellation who either does great things, or teaches how they may be done, or describes them with a suitable majesty when they have been done; but those only are great things which tend to render life more happy, which increase the innocent enjoyments and comforts of existence, or which pave the way to a state of future bliss more permanent and more pure.
Animal experimentation is the blackest of all the black crimes that a man is at present committing... We should be able to refuse to live if the price of living be the torture of sentient beings... I abhor [animal] experimentation with my whole soul. All the scientific discoveries stained with innocent blood I count as of no consequence... The greatness of a nation and its moral progress can be judged by the way its animals are treated.
When it is impossible to stretch the very elastic threads of historical ratiocination any farther, when actions are clearly contrary to all that humanity calls right or even just, the historians produce a saving conception of 'greatness.' 'Greatness,' it seems, excludes the standards of right and wrong. For the 'great' man nothing is wrong, there is no atrocity for which a 'great' man can be blamed.
It is moments like these that force us to try harder, and dig deeper, and to discover gifts we never knew we had - to find the greatness that lies within each of us.
Who can attain to anything great if he does not feel in himself the force and will to inflict great pain? The ability to suffer is a small matter: in that line, weak women and even slaves often attain masterliness. But not to perish from internal distress and doubt when one inflicts great suffering and hears the cry of it that is great, that belongs to greatness.
Pretension may sit still, but cannot act. Pretension never feigned an act of real greatness. Pretension never wrote an Iliad, nordrove back Xerxes, nor christianized the world, nor abolished slavery.