"Mma Ramotswe had listened to a World Service broadcast on he..." — Alexander McCall Smith quote meaning

Mma Ramotswe had listened to a World Service broadcast on her radio one day which had simply taken her breath away. It was about philosophers who called themselves existentialists and who, as far as Mma Ramotswe could ascertain, lived in France. These French people said that you should just live in a way which made you feel real, and that the real thing to do was the right thing too. Mma Ramotswe had listened in astonishment. You did not have to go to France to meet existentialists, she reflected; there were many existentialists right here in Botswana. Note Mokoti, for example. She had been married to an existentialist herself, without even knowing it. Note, that selfish man who never once put himself out for another--not even for his wife--would have approved of existentialists, and they of him. It was very existentialist, perhaps, to go out to bars every night while your pregnant wife stayed at home, and even more existentialist to go off with girls--young existentialist girls--you met in bars. It was a good life being an existentialist, although not too good for all the other, nonexistentialist people around one.