You have experienced other people's lives? How? Are you a discorporated entity that possesses the living?

There's this concept called empathy, and people can share how they experience things. We can also relate our own experiences. So, it might not be a first-hand experience, but we can put ourselves in their shoes. If we see a friend experience something, it becomes a shared experience. When our friends laugh, we laugh too. When they grieve, we grieve with them. Etc