Gödel, Escher, Bach[1] has shaped the way I think in many ways and really warped my perspective on allot of things.

There's also the Imperial Radch series which is a very, very good sci fi series which is unlike any other sf I've ever read[0].

[0]: https://www.goodreads.com/book/show/17333324-ancillary-justi...

>Winner of the Hugo, Nebula, British Science Fiction, Locus and Arthur C. Clarke Awards.

[1]: https://en.wikipedia.org/wiki/G%C3%B6del,_Escher,_Bach