egoism

I went to a lecture about egoism. It was one of the lecture about 'the bad life' of studium generale. Sins. Interesting to see how the philosopher is struggling in words, gets lost in presumptions and exceptions and exclusions to make A point. Other than that it was interesting and it keeps me awake. What is egoism is however still not clear... it depends how you define it. Why is it a sin? because we see it as a sin. Apparently the values we have do not match with someone who acts out of egoism. Would it match our values, than egoism wouldn't be a sin.