The book has been extremely transformative for me at multiple points in my life as I've aged. If I could only recommend a single piece of fiction, it would probably be The Little Prince.

I also highly recommend the 2015 animated film adaptation. It has a rock-solid cast, and presents the classic story within entirely new layers of interpretation that speak to multiple generations at once. It's a real tearjerker that only gets more potent with age.

I'm also not sure why so many commenters here seem confused or negative towards The Little Prince. It is a timeless, culture-invariant treatise on the most precious and important facets of human existence.