Ask HN: What book that you read in 2015 significantly affected how you think?

Mine (they were read in this order, and I have left off many that weren't as good): Zero to One, Poor Charlie's Almanack, Snowball, The Outsiders (8 CEOs, not the fiction novel), Sapiens, Principles by Ray Dalio, Overcoming the 5 Dysfunctions of a Team, The Road to Character

Reading it now, so that technically counts.

"Say this not that." by Carl Alasko

I've gone through a metric shit ton pile of self help and relationship help books in my time. But I think this one, while it repeats some well worn wisdom, it presents them in a concrete enough way that the advice is finally gaining traction in my own head. I think the key is that it presents the advice in real world vignettes as both bad and good idea formats. Like that bone guy on Animaniacs.

Nietzsche's The Birth of Tragedy

Trust Me, I'm Lying by Ryan Holiday. It's Chomsky's "Manufacturing Consent" for the social media age.

Positive Intelligence. I was able to "label" my personality and all of those of my teams and reports. I know how I need to change, and know what drives the people I work with. I never thought of the over achiever as a problem, but they "prevent" others from stepping up. Emotional Intelligence 2.0. Much easier read than the original. We are humans, driven by emotion, we need to be smart about it.