Before Auschwitz, which shattered any previous, optimistic belief about human nature.

Central to this philosophical stance is an essentially optimistic belief in the core dignity of humans, and their ability to transform themselves in a positive way.

In the search for life's origin, Dr. Ponnamperuma was widely known for his optimistic belief that a chemical explanation would be found.

They held to an optimistic belief in the ability of humanity to effect changes for the better in society and nature, guided only by reason.

The West should cease its optimistic belief that China will somehow channel its economic growth toward the institution of Western-style democracy.

What's especially disheartening is the dissipation of the optimistic belief of the 1960's that we had found the solution to our macroeconomic problems.

This novel of marital betrayal is set within a moral framework tempered by Anne's optimistic belief in universal salvation.

It became known as The Model House, in the rather optimistic belief that its inmates would lead a life of model Christianity.

Sothern credited her "optimistic belief" and Roman Catholic faith for getting her through.

It hints that the person referred to is naïve, unaware of reality or deranged in holding such an optimistic belief.