Dangerous ideas

This time we're interested in books that deal with "Dangerous ideas". More so than usual, you are free to interpret the topic any way you see fit! Regardless of your choice, you are cordially invited to briefly present one or more books of any kind (fiction, non-fiction, whatever) that fit within this topic.

Afterwards we will have a casual and friendly chat about the books, about dangerous ideas, and wherever else the conversation takes us!

You are of course welcome to bring the books you want to discuss, but it's also fine if you don't.