In ordinary talk, egoism is used much like egotism: putting yourself first, or being too full of yourself. People say it when they mean someone is self-centred. That is the sense you will hear most.

In ordinary talk平常講話的時候，egoism is used much like egotismegoism跟egotism用法很像：putting yourself first就是把自己放第一位，or being too full of yourself或是太自以為是。People say it大家會這樣說 when they mean someone is self-centred是指某個人很自我中心。That is the sense這是 you will hear most你最常聽到的意思。

There is a more bookish sense as well. In philosophy, egoism is a theory: that people do, or should, act for their own good. That is a claim about how the world works, not just an insult.

There is還有 a more bookish sense as well一個比較書面、學術的意思。In philosophy在哲學裡，egoism is a theoryegoism是一種理論：that people do, or should, act for their own good主張人本來就會、或應該為了自己的利益行動。That is a claim about how the world works這是在講這個世界實際運作的方式，not just an insult不只是一句罵人的話。

Egotism, with a t, is the everyday fault — talking about yourself, showing off, needing to be the centre. Many speakers blur egoism and egotism, and some dictionaries treat them as close, because that is how people really speak.

Egotism, with a tEgotism，中間多了個t，is the everyday fault是日常說的那個毛病 — talking about yourself, showing off, needing to be the centre老愛講自己、愛現、需要當焦點。Many speakers blur egoism and egotism很多人講話時egoism跟egotism分不清楚，and some dictionaries treat them as close有些字典也把它們當成很接近的字，because that is how people really speak因為大家實際上就是這樣講話。

If you are reading a philosophy page, look twice.

If you are reading a philosophy page如果你在讀哲學的文章，look twice要多留意一下、看仔細一點。