Looking back on his long and luminous life at age ninety-three, the great cellist Pablo Casals held up one great task before humanity: “to make this world worthy of its children” — those inheritors of the present and living emissaries of the future, whose souls, in Kahlil Gibran’s memorable words, “dwell in the house of tomorrow.” To make of that house a harmonious home — for our own children, and the children of every platypus and every redwood — is the one great calling that unites us all across the infinite divides of our fractured present.

One small country, in which 0.0002% of the world’s population lives in one of the planet’s most biodiverse habitats, has taken it upon itself to model for the rest of humanity an inspired step along the path forward.

In 1981, just after a dazzling new species of nautilus was discovered in its turquoise waters, the Republic of Palau — a tiny, vast-spirited Pacific island nation midway between Australia and Japan, crowned with coral castles and radiant with otherworldly jellyfish — voted for the world’s first constitutional ban on nuclear and biological weapons, overriding political pressure from the titanic United States to continue testing and storing its own nuclear arsenal there.

A generation later, Palau revised its immigration policy to become Earth’s first country with an ecological pledge, stamped into the passport of every visitor.

In an especially wise and soul-warming choice, the poetic pledge signed upon entering Palau is addressed to the children of the islands. It reads:

Children of Palau,

I take this pledge, as your guest, to preserve and protect your beautiful and unique island home.

I vow to tread lightly, act kindly and explore mindfully.

I shall not take what is not given.

I shall not harm what does not harm me.

The only footprints I shall leave are those that will wash away.

Complement the Palau pledge — which appears in Cynthia Barnett’s altogether magnificent eco-social serenade to the seas, sung through the evolutionary and cultural history of seashells — with the Einstein-Russell manifesto for healing an ailing and divided world, then revisit this lovely French picture-book envisioning a more possible world for the children of tomorrow.