I'm including him here because I'm not even sure how much his theology influences me. Probably a lot. I grew up in a denomination that his theology heavily influenced. I went to private schools created by that denomination. I willingly took a class on Calvin's theology in seminary, and professors included his opinions throughout every phase of my education. Even if I had wanted to, I could not have escaped his influence.
As it happens, I don't really want to escape it. Calvin, like any good theologian, considers humankind as well as God in his theology. I find the sociology contained therein sensible though not complete.
Calvin considers human beings imperfect and incapable of becoming perfect by their own efforts. Without God stepping in to stop them, human beings will create horrors. Fortunately God does step in, but God does not take away the human capacity to do evil. Instead he resurrects the human capacity to do good. God doesn't even give all humans this ability. God chooses whom to save.
I'm not going to argue about whether or not I think Calvin's theology right or wrong. I'm just stating that it lies under my beliefs about much of life.
Calvin's theology leads me to be suspicious of the human animal while simultaneously trusting of the universe as a whole.
Humans, following Calvin's thought, are not perfect and will not become perfect. All humans carry within them the seed of disorder, the potential to cause pain and disaster for themselves and others. Simultaneously they also bear the image of God and the potential for innovation and healing. If you're a Calvinist, you never know which to expect in others and to be honest, I expect a mixture of both.
I expect people to have good motives for their actions and the capacity to twist them as well. I also believe God does have complete power over the universe and the ability to turn disaster into something better. As far as sociology goes, it means that I find humans unpredictable and the universe as a whole wonderful and infinitely surprising. It also means that I dismiss rather quickly both the idea that humans will become endlessly better and better as well as the idea that humanity falls ever deeper into some black pit of depravity.
Seems sensible to me.