Lost Connections is about the social causes of mental illness, and it introduces some leftish ideas (workplace democracy, direct organizing to prevent eviction, universal basic income) without seeming radical or using scary words. It is a great Trojan horse for these concepts and a good introduction to the alienation of capitalism overall.

I'll just let the top Amazon review speak for itself:

The nine causes of depression form the foundation for the big set up after the halftime show. They appear well thought out, researched and relevant to today's society. You are essentially hooked and have no choice but to eagerly consume the final act, which is the re-connections. Here in lies the trap. Mr Hari, albeit well intentioned and I believe sincere, exposes the subliminal message which is to advocate for a Socialist welfare state where the value and dignity of self-reliance is shunned and quietly frowned upon.