The value of co-operation in human society is that the idleness of all its members is raised through their shared efforts. In a division of labour, each member is allotted some task to perform on behalf of society: to carry water, to sweep streets, to cook food. This division of labour regularly results in time savings. Rather than ten people going to a well or stream for the water each needs, one person goes and fetches all the water that ten people need, saving nine journeys. Rather than ten people each cooking their own food, one person cooks for all ten, saving the other nine the chore.

But in such co-operative societies, people must be able to rely upon those assigned their various tasks to carry them out. If the cook neglects to prepare food, everyone has to fall back on their own devices. Those who work in society must be diligent and dependable. If they promise to carry out some task, they must keep their promise.

It is ultimately self-interest that motivates individuals to work co-operatively within society: each lives an idler life within society than without it. If this were not the case, society would dissolve. But while self-interest is the primary motive, within co-operative society, each individual must also be concerned with the interests of others. In a division of labour, the cook must have care and concern for the water carrier and the road sweeper, for he depends upon them as they depend upon him. It is not just trouble for the water carrier if he falls and breaks his leg, but also trouble (traballo - travail - work) for the whole society he serves. And when he recovers and resumes his duties, it is not only in his benefit, but also to the benefit of his society.

Therefore in co-operative society there will not only be self-interest, but care and concern for the interests of others. It is not simply the water carrier's duty to haul water from the well, but it is also necessary that in all his social interactions he act with care and consideration for others. For if he diligently hauls water as required, but the rest of the time is obstructive, abusive, and inclined to fight, then the benefit he gains for society as water carrier may be entirely outweighed by the damage he causes at other times.

Each must be considerate of others. To observe customs is to be considerate of others. To tell the truth is to be considerate of others. To keep promises is to be considerate of others. To work diligently is to be considerate of others.

The considerate man is concerned not only with the effects of his actions upon himself, but the effects upon others. A considerate man is concerned with his own self-interest, but he will act as far as he can not to damage the interests of others. While he is concerned to gain by his actions, he is equally concerned that others should not lose because of them. A considerate man weighs up the costs and benefits of an action to everybody, and will not carry it out if he sees that someone will be damaged by it. A considerate man will also carry out acts which benefit him little or nothing, but benefit others considerably, calculating that the net social benefit outweighs his loss. Thus a man might move fallen stones obstructing a road, not because it benefits him to do so, but because it will benefit everyone else who uses the road. Or a man might put out a fire, not because he personally benefits from it, but because he considers that the fire might cause great damage to others.

When an inconsiderate man thinks to light a fire to burn some waste, he weighs up the costs and benefits to himself alone. But when a considerate man thinks to light the same fire, he also considers the effects on others. If he sees that the smoke is likely to soil washing hanging out to dry, or slow and obstruct passers by, or make breathing difficult for them, then he may decide that their loss outweighs his gain.

It may not always be others who benefit by the actions of a considerate man. While there must be a general prohibition upon theft in society, the benefit to a starving man of a loaf of bread will generally outweigh the loss to its baker. For the gain to the starving man is the continuation of his life, and the loss to the baker is a few minutes work. And therefore in such circumstances theft is the appropriate course of action.

The considerate man is neither selfish nor selfless. A selfless man who never considers himself, but only considers the interests of others, is as likely to cause himself loss and damage as a selfish man concerned with his own self-interest is likely to damage others. And ultimately, in damaging himself, he damages others.

The most virtuous members of society are therefore those who, in all that they do, act with consideration both for themselves and for others.

Not every member of human society was ever perfectly virtuous. It has always appeared obvious to thieves that it is easier for them to simply steal what they want rather than earn it through honest work. And they have always been equally blind or indifferent to the fact that their theft imposes costs upon those from whom they steal: that their gain in idleness entails a loss of idleness for others. Nor do they ever consider that if everybody stole everything they wanted, human society would collapse, and every member of it be reduced to unrelenting toil and perhaps death. The vice of thieves is to consider only their own interests, and to lack consideration for the interests of others.

And therefore human society has always been made up of both considerate and inconsiderate people. The inconsiderate, who consider only their own interests, generally profit at the expense of the considerate. And for this reason at least, human societies are usually made up of the inconsiderate rich living off the considerate poor - by theft, embezzlement, racketeering, prostitution, protection, and the like. And in the extreme, society becomes divided into masters and slaves, the former leading largely idle lives at the expense of slaves leading extremely busy lives.

At the heart of all vice - as opposed to virtue - there lies lack of consideration. For if theft is inconsiderate, so also is vandalism, murder, slavery, and rape.

Or else, one autonomous human society might exercise consideration for its own members, but lack consideration for the members of other autonomous human societies.