 When Seneca discusses how we must hold on to the insight that only virtue is good, in order to improve ourselves, it may sometimes seem as if he blamed the world (competition, superficial lifestyles, etc.) for the difficulty of the task. But ultimately, Seneca argues that we are standing in our own way. He tells his addressees that, by living in such-and-such a way, they weigh themselves down (‘tibi gravis eris’; On Peace of Mind 3.6), or become a problem to themselves (‘tu tibi molestus es’; Letter 21.1). It is with a view to this reflective engagement with one’s thought that Hadot finds ‘spiritual exercises’ in Roman Stoic philosophy (P. Hadot 1995, 79–144; cf. Letter 6.1 on self-transformation).