I think that philosophy just helps you reinforce and define your belief system in general, to live more true to your core beliefs, for better or worse. It has to be (unfortunately) pretty rare that someone reads about a philosophical concept and completely turns around on a core belief.

Philosophy to some becomes more of a faith. They believe their way is correct, despite anything. They cement their ideas because people in the past have thought that way too. Once someone finds a philosophy that makes sense to them, they often dive very deep into it.

The point of philosophy, imo, is to become more open-minded and to question the nature of things out of curiosity. And this post says ‘toolkit’ because there’s more than one tool.

Taking stoicism as one branch of philosophy, it teaches you that you are the only one you can control. Accepting that can help someone cope with stress. However, someone who is always stoic and makes it the center of their opinions and identity are doing themselves a disservice. Because it closes their mind to the many tools and ideas other philosophies can give you to cope with life. One major downside to stoic philosophy is it promotes an individual mindset and discourages being vulnerable with others.

One needs to draw inspiration and thought from different sources, in order to create well-rounded critical thinking. Your friend probably found that corner of philosophy that made them feel understood and justified in the way they live. Sadly, that’s all they used it for. But the tools of philosophy remain there for anyone to find and use in many different ways.

Socrates or someone said: Freedom is the ability to change one's mind when one hears a better argument. Maybe you need to lay your case out a little better to your buddy. See if he is free.