Charity, or love, is not an option for Christians, he said, and "practising charity in truth helps people understand that adhering to the values of Christianity is not merely useful, but essential for building a good society and for true integral development," he wrote.

In addressing the global economic crisis and the enduring poverty of the world's poorest countries, he said, "the primary capital to be safeguarded and valued is man, the human person in his or her integrity."

The global dimension of the financial crisis is an expression of the moral failure of greedy financiers and investors, of the lack of oversight by national governments and of a lack of understanding that the global economy required internationally recognized global control, Pope Benedict said.

"In the face of the unrelenting growth of global interdependence, there is a strongly felt need, even in the midst of a global recession, for a reform of the United Nations organization, and likewise of economic institutions and international finance, so that the concept of the family of nations can acquire real teeth," the Pope wrote.

"To manage the global economy; to revive economies hit by the crisis; to avoid any deterioration of the present crisis and the greater imbalances that would result; to bring about integral and timely disarmament, food security and peace; to guarantee the protection of the environment and to regulate migration: for all this, there is urgent need of a true world political authority."

Pope Benedict insisted that the idea of the world's richest nations scaling back development aid while focusing on their own economic recovery overlooked the long-term economic benefits of solidarity and not simply the human and Christian moral obligation to help the poor.

"In the search for solutions to the current economic crisis, development aid for poor countries must be considered a valid means of creating wealth for all," he said.

The economic growth of poorer countries and their citizens' demands for consumer goods actually benefit producers in the world's wealthier nations, he said.

Pope Benedict said food and water are the "universal rights of all human beings without distinction or discrimination" and are part of the basic right to life. He also said that being pro-life means being pro-development, especially given the connection between poverty and infant mortality, and that the only way to promote the true development of people is to promote a culture in which every human life is welcomed and valued.

"The acceptance of life strengthens moral fibre and makes people capable of mutual help," he said.

He said the environment, life, sexuality, marriage and social relations are inextricably united. If society does not respect human life from its conception to its natural end, "if human conception, gestation and birth are made artificial, if human embryos are sacrificed to research, the conscience of society ends up losing the concept of human ecology and, along with it, that of environmental ecology," he said.

Development programs and offers of aid that encourage coercive population-control methods and the promotion of abortion do not have the good of people at heart and limit the recipients' motivation to become actors in their own development and progress, the Pope said. In addition, an anti-life mentality in the world's richest countries is related to the lack of concern for the poor.

"How can we be surprised by the indifference shown toward situations of human degradation when such indifference extends even to our attitude toward what is and is not human?

"While the poor of the world continue knocking on the doors of the rich, the world of affluence runs the risk of no longer hearing those knocks on account of a conscience that can no longer distinguish what is human," he said.

Pope Benedict also emphasized church teaching that making money and being wealthy are not sins, but that the way the money is made and the way it is used can be.

The encyclical condemned corruption, the exploitation of workers, the destruction of the environment, the continuing practice of wealthy nations imposing such high tariffs on imports that they shut poor countries out of the international marketplace and, especially, an "excessive zeal" for enforcing patents, especially on medications that could save the lives of thousands of poor people if they were available at a reasonable cost.

Pope Benedict called for "a profoundly new way of understanding business," which recognizes that investors are not a company's only stakeholders, no matter how the business is structured and financed. Employees, those who produce the raw materials, people who live in the communities where the company is based, where its products originate and where its products are sold all have a stake in the business, the pope said.

The English version of the Pope's encyclical can be found at www.vatican.va/holy_father/benedict_xvi/encyclicals/documents/hf_ben-xvi_enc_20090629_caritas-in-veritate_en.html .