A common (mis)understanding of John Rawls is that he thinks it is entirely arbitrary who is born with which talents. We do not in any sense "deserve" our natural intelligence, charm, or good looks, and so there is no particular moral reason why these traits ought to be rewarded.
My reaction to this line of argument is to complain that this threatens to entirely strip away our moral agency. No-one "deserves" their moral character; does this mean we should abandon anything beyond the most unambitious conceptions of free will and moral responsibility? If so, then what is the point of doing moral theory at all?
But in fact Rawls' critique is more subtle than that. The idea is not that our talents are arbitrary, but rather the value which society places on those talents is arbitrary. It may be a necessary fact about me that I have an aptitude for political philosophy; it surely isn't a necessary fact about me, about Hungary, or about anything else that as a result of that talent there is a university willing to provide me with free education and accommodation.
The question, then, is what would render non-arbitrary the value placed by society upon a particular ability? If every society in existence values something, is that sufficient to show that the value is non-arbitrary? If societies which value a particular trait tend to provide better lives for their members, is that sufficient to show that the value is non-arbitrary?
If either of these cases is met, then we can empirically rebut Rawls. Intelligence - which is admittedly more a suite of skills than a single skill, but they're all strongly correlated - is useful across a very wide variety of contexts. (Fluid intelligence even predicts people's reaction times, so being intelligent would even be useful in a warrior society with status determined by fighting ability). Maybe it's arbitrary that I get paid to do Philosophy rather than Physics, Poetry or Philology, but thanks to the magic of the g-factor we know that someone who is much-better-than-average at one of these will probably also be better than average at the best.
What about looks? Surely the social preference for good-looking people is arbitrary? Well, I think that's a poor framing. Is it arbitrary that societies particularly benefit men if they are tall with highly symmetrical faces? Is it arbitrary that societies particularly benefit women if they have long hair, symmetrical faces, large breasts, a thin waist and wide hips? Those would describe people considered good-looking in every society we have encountered, with good evolutionary reasons - typically these features indicate good health and nutrition over an extended period of time, combined with low mutational load. What's more, our undue propensity to benefit these people is caused primarily by unconscious biases. You could have a society which was not unequal in these people's favour, but the inhabitants of such a society would not be human.