Optimism means having a hopeful and positive outlook on life. It is believing that good things will happen and focusing on the bright side even when things are difficult. Full definition
There was a sense of optimism about the missionary enterprise which prevented any questioning of the motivation of mission or of the missionary message. (religion-online.org)
Despite dealing with many of these lingering issues heading into 2011, there is still plenty of reason for optimism for buyers and a brighter future in store for sellers. (gotbaltimorehomes.com)
They had a down - deep sense of optimism about their future, and this drove their determination to succeed in the process. (sciencemag.org)