Between pessimism and optimism is being.
As a lifelong optimist, l exist. (pinches self to check)
Being (dictionary.com)
noun
the fact of existing; existence (as opposed to nonexistence).
conscious, mortal existence; life: Our being is as an instantaneous flash of light in the midst of eternal night.
substance or nature: of such a being as to arouse fear.
something that exists: inanimate beings.
a living thing: strange, exotic beings that live in the depths of the sea.