Nonetheless , his contributions thereafter were profound .
But , while Clark independently arrived at a marginal utility theory , he did little to advance it until it was clear that the followers of Jevons , Menger , and Walras were revolutionizing economics .
Menger 's contributions thereafter were profound .
But , while Clark independently arrived at a marginal utility theory , he did little to advance it until it was clear that the followers of Jevons , Menger , and Walras were revolutionizing economics .