Ask Lemmy

The awakening of intelligence by Jiddu Krishnamurti

Aldous Huxley's Island. Something to aim for.

Also, it's been a while since I read it, and it's a bit didactic, but Daniel Quinn's Ishmael. It's about a telepathic gorilla, and it had the capacity to blow minds.

Oh the places you'll go!
Dr Seuss

The Jungle. Coal. Ubik. Catch 22. HHGTTG.

The ones that influenced me the most earlier in life was

• The Unbearable Lightness of Being, by Milan Kundera
• sapiens, by yuval noah harari

Both illuminate what it means to be human and what makes us (not) achieve happiness, but explained through very different lenses

The Crying of Lot 49 — it's pretty short.

Capital and ideology by Thomas Piketty. An eye opener on wealth distribution throughout history and the arguments that held societies together to allow wealth disparity.

Paris in the Terror by Loomis

Describing public events and the private machinations behind them (through the participant's journals and letters), revealing how the road to hell is paved with the best of intentions.

The Tragedy of the Moon by Asimov.

Edit: And one more because why would be only one?
A Short History of Nearly Everything

I think you'd have to pick something more geared towards children as books for older people will potentially be too narrowly focused or infused with cultural or regional influences.

Something like the giving tree has some good staying power and discuss concepts that should be beneficial across time/cultures/religions.

Ishmael by Daniel Quinn

Brothers Karamazov

Doctor Zhivago

To Kill A Mockingbird

Narnia series

Sundown Towns

The Remains of the Day by Kazuo Ishiguro

Absolutely beautiful book

Scuppers the Sailor Dog

Hagakure.

Different people like different books.

• The Denial of Death by Ernest Becker

Perhaps you could dismiss it as having too much of a Western focus, but it really was an eye opening book that made me reexamine various cultural institutions at the time I read it

It should probably be a book the reading of which would be most beneficial to everyone. That’s a high bar pointing to some form of practical philosophy. I’d go with an introduction to Buddhism, something like What the Buddha Taught by Walpola Rahula though perhaps there are others better suited for a general audience.

Reading isn't about any single book. Each book is a peice in a larger concept of expanding ones mind outside the small part of the world they live in. Some expand more than others. But one alone makes only a small difference.