>>715288006
Most of the time you can just straight up look it up. We live in an era where it's common for people to have massive swathes of their life available as public information, and public personalities are expected to share much of that info for business reasons.
Even accepting that you can't know everything about a person though and that there're a lot of cases where you can't do this, you can typically make a pretty good read just off of the writing itself, especially if you have any personal experiences to compare it with. The people who typically turn out to be pretty fucked up tend to tell very raw stories, intimate stories about tragedy. The people who're speculative are usually much more abstract, clinical, and can't really help but frame it from their own point of view.
Sometimes it turns out someone who's had it easy is just very good at capturing the real feeling and sometimes someone who's had it tough isn't good at communicating it but any time you're iffy on something, look up the writer. Your gut instinct will be right almost 100% of the time that you're able to find enough to confirm the truth. It's just normal that writers always frame works from their own life.
