How to Use "optimist" with Example Sentences

1. He is a natural optimist but sounded unusually low .
2. Did you know there was an organization of and for optimists called optimist international ?
3. The chief justice is also an optimist , arguing that you " must trust human beings ; with friction there is energy . "
4. Which are you an optimist or a realist ?
5. Gilding is actually an optimist at heart .