His advice resonates with people of all ages, notably our switched-on and maybe even striking schoolkids, but naturally makes more sense to those who can actually afford to live the way they want.

Because no matter how much you care about the fate of the ice caps or orangutans, they must inevitably slip down your list of priorities if you spend most of each day worrying about how you are going to put food on the table for your family.

We live in a supposedly rich country but it has more food banks than branches of McDonald’s, and 4.1 million children are classified as living in poverty – a situation made far worse by the disastrously botched introduction of Universal Credit.