What is the source of this extreme self-confidence found in almost all optimists, this conviction that they can accomplish great things?

几乎所有的乐观主义者都坚信他们能成就大事，乐观主义者的这种极端自信源自何处？

youdao

"Obama's ability to convey his feelings of self-worth to others may have helped him project the image of competence and confidence that voters found so compelling," Zeigler Hill told the Digest.

奥巴马有把他对自身价值的感觉传达给别人的能力，也许是这种能力帮助他规划出了让选民们如此信服的富有能力与自尊心的形象。

youdao

They found that those who had been given the commercial fragrance showed an increase in self-confidence.

他们发现，那些喷有正常气味香水的人自信心明显增强。

youdao

It is not going to shed its new-found self-confidence and assertiveness just because of a few speeches.

ECONOMIST: Russia and the West: In search of a Putin policy | The

This is a company which has had its fair share of critics in the past few years (not least from those who, like Clarkson himself, lobbied the company to provide ADSL in their area), so it may be feeling refreshed by this new-found self-confidence.

BBC: AD BREAKDOWN

In UK schools, researchers found low levels of self-confidence among disadvantaged pupils, when asked about their approach to a science topic.

BBC: UK pupils 'among least likely to overcome tough start'