John Guillebaud should lead by example and kill himself.

I don't say that lightly.

Guillebaud is a professor emeritus of family planning at University College London. This means that he's old. His most productive years are behind him, but he has a cause.

"The greatest thing anyone in Britain could do to help the future of the planet would be to have one less child."

In his latest comments, the academic says that when couples are planning a family they should be encouraged to think about the environmental consequences.

"The decision to have children should be seen as a very big one and one that should take the environment into account," he added.

I think the decision to have kids is a very big one, but the environment is probably the last thing a couple should consider.

However, since Guillebaud is so enlightened he should lead by example and stop all of his carbon emissions.