Among other obstacles to his optimistic philosophy, it falls to Leibnitz to consider the number of the eternally damned.  That it is infinitely greater, in our human case, than that of those saved he assumes as a premise from the theologians, and then proceeds to argue in this way.  Even then, he says: 

“The evil will appear as almost nothing in comparison with the good, if we once consider the real magnitude of the City of God.  Coelius Secundus Curio has written a little book, ’De Amplitudine Regni Coelestis,’ which was reprinted not long ago.  But he failed to compass the extent of the kingdom of the heavens.  The ancients had small ideas of the works of God. ...  It seemed to them that only our earth had inhabitants, and even the notion of our antipodes gave them pause.  The rest of the world for them consisted of some shining globes and a few crystalline spheres.  But to-day, whatever be the limits that we may grant or refuse to the Universe we must recognize in it a countless number of globes, as big as ours or bigger, which have just as much right as it has to support rational inhabitants, tho it does not follow that these need all be men.  Our earth is only one among the six principal satellites of our sun.  As all the fixed stars are suns, one sees how small a place among visible things our earth takes up, since it is only a satellite of one among them.  Now all these suns may be inhabited by none but happy creatures; and nothing obliges us to believe that the number of damned persons is very great; for a very few instances and samples suffice for the utility which good draws from evil.  Moreover, since there is no reason to suppose that there are stars everywhere, may there not be a great space beyond the region of the stars?  And this immense space, surrounding all this region, ... may be replete with happiness and glory. ...  What now becomes of the consideration of our Earth and of its denizens?  Does it not dwindle to something incomparably less than a physical point, since our Earth is but a point compared with the distance of the fixed stars.  Thus the part of the Universe which we know, being almost lost in nothingness compared with that which is unknown to us, but which we are yet obliged to admit; and all the evils that we know lying in this almost-nothing; it follows that the evils may be almost-nothing in comparison with the goods that the Universe contains.”

Leibnitz continues elsewhere:  “There is a kind of justice which aims neither at the amendment of the criminal, nor at furnishing an example to others, nor at the reparation of the injury.  This justice is founded in pure fitness, which finds a certain satisfaction in the expiation of a wicked deed.  The Socinians and Hobbes objected to this punitive justice, which is properly vindictive justice and which God has reserved for himself at many junctures. ...  It is always