Mental superiority of any kind is at present everywhere so much below the demand; there is such a deficiency of persons competent to do excellently anything which it requires any considerable amount of ability to do
 John Stuart Mill, The Subjection of Women (1869). copy citation

Context

“Where there is now one person qualified to benefit mankind and promote the general improvement, as a public teacher, or an administrator of some branch of public or social affairs, there would then be a chance of two. Mental superiority of any kind is at present everywhere so much below the demand; there is such a deficiency of persons competent to do excellently anything which it requires any considerable amount of ability to do; that the loss to the world, by refusing to make use of one-half of the whole quantity of talent it possesses, is [Pg 154] extremely serious. It is true that this amount of mental power is not totally lost.” source