The author is thinking about the third millennium, which has no name yet. He calls it enviromillennium although, as he states, all other millennia since the life origination on the Earth about four milliard years ago, were also enviromillennia. He brings the attention to the common genetic origin of all organisms including Man. That is why they are mutually dependent and vulnerable. However, Man of the 3rd millennium does not always realise this. At the end the author calls on readers to recognise civilisation limits within the extent of the sustainable development.