If you could send one piece of knowledge back to the Stone Age, what would it be? Assuming you’re making this decision for the good of humankind rather than scheming to make yourself rich, your answer will likely depend on your definition of human progress. You’ve got options. You can right a historic wrong. Introduce life-saving technology centuries early. Expedite a social revolution of your choice. You should try to offer something concrete and practical, but forget about everyday gadgets: What’s the point of a smartphone or ventilator if the tools and knowledge required for production are still millennia away?1 Better than a product is an idea. Press fast-forward on humanity’s greatest discoveries, and offer a head start on flight, radio or antibiotics. Or This story is from Kinfolk Issue Thirty-Seven Buy Now Related Stories Arts & Culture Issue 36 Trivial Matters On the uses of useless knowledge. Arts & Culture Issue 27 Akram Khan On the uneasy dance between knowledge and information. Arts & Culture Issue 45 Yoga with Adriene The internet’s best friend is—finally—finding her own flow. Arts & Culture Garden Issue 45 Piet Oudolf The Dutch designer bringing life—and death—to traditional gardens. Arts & Culture Issue 45 Thomas MacDonell The conservationist transforming the Highlands. Arts & Culture Design Issue 45 The New Craftsmen From the Outer Hebrides to central London, Catherine Lock is celebrating the crafts heritage of Great Britain.