He was a wise man that Seneca. In his letters to his nephew he wrote about many subjects we should dwell upon such as wealth, wisdom and even death. Seneca realised that we spend so much time worrying about death that the life we are left with is worse than the death we fear so much.
Milton hit the nail on the head as well when he said
I’ve come to realise this when I’ve seen people who should be miserable (by my expectations) actually act very happy and vice versa. People with no money and nowhere to live were overjoyed and people with all the money and?possessions?were acting as if they had the weight of the world on their shoulders.
Now I understand. No matter what is going on outside, it is out interpretation of it which determines how we feel.