When we imagine our Universe to be just one out of a multitude of possible worlds we devalue this world, the one we see, the one we should be trying to explain.

The Amazon is not just a set of trees. It is a set of 25 million people. If we don't create real economic opportunities for them, the practical result is to encourage disorganized economic activities that results in the further destruction of the rain forest.

The scientist should treasure the riddles he can't solve, not explain them away at the outset.

Social solidarity must rest instead on the sole secure basis it can have: direct responsibility of people for one another. Such responsibility can be realized through the principle that every able-bodied adult holds a position within the caring economy - the part of the economy in which people care for one another - as well as within the production system.

In a world of democracies, the most deserving basis of national differences is that the different states of the world should represent a form of moral specialisation within humanity.

Brazil has no future as a China with fewer people.

When we imagine our Universe to be just one out of a multitude of possible worlds we devalue this world, the one we see, the one we should be trying to explain.