Is it an argument? Isn't it more an observation to which many can attest? Musical ability (for instance) is one area where it's completely clear cut. Even if you fingered fugues on the piano reaching out from your cot at age 18 months, you'll never get very far in the extraordinarily demanding world of classical music unless you're prepared to work like a dog. Ask Evgeny Kissin, one of the most prodigiously talented pianists alive today.