Technical mastery of the occupation of playwriting, criticism, or statesmanship, will require more specifically intellectual qualities than will be demanded by the competent musician or painter.
But no matter how much intelligence may be needed, the way in which it should be used remains the same.

Mere industry, aspiration, or a fluid run of ideas make as meager an equipment for a politician, a philanthropist, or a critic as they would for an architect; and absolutely the most dangerous mistake which an individual can make is that of confusing admirable intentions expressed in some inferior manner with genuine excellence of achievement.

If such men succeed, they are corrupting in their influence.

If they fail, they learn nothing from their failure, because they are always charging up to the public, instead of to themselves, the responsibility for their inferiority.
The conclusion is that at the present time an individual American's intentions and opinions are of less importance than his power of giving them excellent and efficient expression.

What the individual can do is to make himself a better instrument for the practice of some serviceable art; and by so doing he can scarcely avoid becoming also a better instrument for the fulfillment of the American national Promise.
To be sure, the American national Promise demands for its fulfillment something more than efficient and excellent individual instruments.