I read Zen and the Art of Motorcycle Maintenance three times.
The first time I read it, I thought it was the best book ever and it got me reading Plato and interested in eastern religions and philosophy. I also had a flurry of interest in zen-influenced physics books (Dancing Wu Li Masters, The Tao of Physics).
The first time through, Zen and the Art took my breath away.
I went back and re-read it about 10 years later and appreciated its depth even more now that I understood physics and Zen and Taoism and Plato. The second read was profound and filled me with wonder.
I also went back and re-read Dancing Wu Li Masters and The Tao of Physics and found them to be juvenile nonsense. I was embarrassed to have recommended them to other people.
On my third reading, I decided that Zen and the Art was juvenile nonsense too but it still has a special place in my memory. If it weren’t for this book, I would never have fallen in love with physics and philosophy – a love that endured.
Of the eastern mysticism stuff, the only thing that stuck was the Tao Te Ching. I read it often.