‘You may take a ton of coal and warm a house with it. The heat-energy of the coal is transformed, set free, and directed to a certain purpose. But if you try to warm the house by means of open coal fires in old-fashioned fire-grates, you will warm the chimneys and some of the air above the chimneys--and yet the rooms of the house will not be appreciably warmer than they were when you began. On the other hand, you may take a ton of exactly the same kind of coal and by means of a steam-heating system in the cellar warm the rooms of the house to such an extent that you have to wear your summer clothes in the depth of winter. The steam-heating system, however, has not increased the heat-energy of the coal; it has merely set free, utilised, and directed the heat-energy of the coal in a common-sense--that is to say, a scientific--manner. No amount of common sense and ingenuity will get as much heat-energy out of half a ton as out of a ton of coal. You may devise the most marvellous steam-heating system that exists on this side of the grave, but if there is no fuel in the furnace, or if there is in the furnace a quantity of coal inadequate to the size of the house, the house will never be comfortable except for polar bears and lovers. The available coal is the prime factor. ‘Well, an individual is born with a certain amount of energy--and no more. Just as you cannot pour five quarts out of a gallon (as a rule, you cannot pour even four quarts), so you cannot extract from that individual more energy than there is in him. And, what is more important, you cannot put additional quantities of energy into him. You may sometimes seem to be putting energy into him, but you are not; you are simply setting his original energy free, applying a match to the coal or fanning the fire. An individual is an island on whose rocky shores no ship can ever land that most mysterious commodity--energy. You may transfuse blood, but not the inexplicable force that makes the heart beat and defies circumstance. ‘Some individuals appear to lack energy, when, as a fact, they are full of energy which is merely dormant, waiting for the match, or waiting for direction. Other individuals appear to lack energy, and, in fact, do lack energy. And you cannot supply their need any more than you can stop their hair from growing. ‘No, young lady; it is useless to interrupt me by asking me to define what I mean by the word “energy.” To define some words is to cripple them. You know well enough what I mean by energy. I mean the most fundamental thing in you. ‘Being a reasonable woman, you admit this--and then go on to demand, first, how you can be quite sure whether you have been born with a large or medium or a small quantity of energy, and, second, how you can be quite sure that you have not lots of energy lying dormant within you. You cannot be quite sure of anything. This is not a perfect world.