I´m a thinker because I like to be with myself over the years and many times I prefer to go for a walk with my dog than to meet with friends. I regard me myself as an observer of everything that happens around me.
I see what you mean! One's own company can be the best context to reflect upon so many things...from the meaning of life to what is going to be on today's menu! As you consider yourself to be an observer, I'm sure you have an eye for detail, as we say in English!