Philip Gilbert Hamerton, “Amateur Painters,” Thoughts About Art (Boston: Roberts Brothers, 1882), pp. 356-357:
The argument that an amateur with leisure at his command has not time to study painting seriously may be met by the reply, that since many painters have painted well in their youth it does not need a lifetime to learn the manual practice of the art. It appears to cost about seven years’ labour, when the whole time is given, being equivalent to an outlay of about 14,000 hours. This is a great outlay of time; but suppose the case of a youth who inherits a fortune, and, having finished his university education, takes to studying art as an amateur. He may expect to paint well at the age of thirty, if he goes through the regular training, and at thirty a man is still young. This, however, supposes the most ambitious amateurship, that which aspires to paint pictures. There are various gradations of less ambitious but equally serious amateurship, which do not require so considerable an expenditure of time. Suppose the case of an amateur who confines himself to drawing, not attempting colour at all; he may learn to draw well in from 5,000 to 7,000 hours, say three hours a day for seven years. Here, again, he may be less ambitious. This estimate is based on the supposition that he draws the figure, and qualifies himself for severe figure-design. But he may draw sufficiently accurately for animals and landscapes with less labour, and for purposes of illustration not having artistic quality for an object with less labour still. One may do thoroughly useful and valuable scientific illustrations or topographic memoranda without having given the time necessary to reach the subtleties of art.