Obviously...
Obviously, if it were not for these various parts, Apollo would never have come into existence, and it would not have been able to overcome the difficulties facing man on his way to the moon. This example shows us that in a whole whose parts are connected with each other and in harmony, variety cannot be avoided. Now let us look at the world of existence to discover that diversity here is neither pointless nor without reason.
Without doubt, the beauty and complexity of this world is due to the variety of its parts, and we cannot call this diversity meaningless or unjust. We have shown above that injustice exists where distinction is made when all have the same right to use something equally. However, the parts of the world had no existence before they were created, and so they had no pre-existent rights which would enable us to say that the distinctions between them constitutes an injustice.
In fact, the world of creation owes its existence to variety, and if there had not been any variety there would not have been any universe, there would have been just one big uniformity. It was this variety that brought into existence atoms, solar systems, galaxies, trees, plants and animals. Turning now towards variety in human life, we see that diversity in man is not an exception to this general principle of variety.
If we look at the diversity in human ability, intelligence and memory and ask why they are not the same in all humans, we must first ask why plants and minerals do not have these superior faculties. Then we can see that neither of these questions can be properly discussed, because such questions can only arise when rights are being trampled on. In this case, neither of these two conditions existed prior to creation such that a distinction between them should be seen as an injustice.
Another point to notice is that God demands from everyone according to his ability and responsibility, and no one is asked to do more than his bodily and mental powers enable him. This is justice itself. For example, if a principal gives the examination of the most advanced class to one of the lower classes, this is an act of injustice.
However, if he gives the easy questions to the lower class and the difficult questions to the advanced class, then no one can complain that there had been injustice. Instead, he would be regarded as just by any meaning of the word.