The Stoic discipline of action, which is connected to the virtue of justice, says that we ought to treat others fairly and we should engage in social and political activity. This is further supported by the Stoic idea of cosmopolitanism, and by the famous "circles of concern" identified by Hierocles, who counseled that we should refer to other people as brothers and sisters, to constantly remind ourselves that we are members of the same human family.

In my mind, there is no reason why Stoicism shouldn't become as popular as Buddhism, especially in the Western world, where the dominant culture, Christianity, itself absorbed a large number of elements from Greco-Roman Stoicism.

I don't see any Stoic practice as problematic or risky, but I would advise to engage in extreme versions of the negative visualization exercise only if you are an advanced practitioner. The negative visualization is a meditation during which you visualize, slowly and deliberately, something bad or discomforting happening to you.

Often we can change things, and a realistic attitude - including envisioning worse case scenarios - actually helps to accomplish that change. But if you truly cannot do anything about something, then why on earth would you want to make things even worse for you by falling into despair? It seems like adding a self-inflicting injury to the already existing one.

If a theory purports to explain everything, then it is likely not explaining much at all.

Death itself is a natural occurrence, it is unavoidable, and the Stoics thought that part of philosophical practice is to get comfortable with the unavoidable, learning to face it with courage.

... it is because one can build a compelling set of arguments - informed by science and thoroughly compatible with it - that to believe in anything despite the complete lack of evidence is, in fact, irrational.