Marx, (Karl, not Groucho), Freud, and Darwin. I was reading an article about the dawning of "the age of enlightenment," secularism, and materialism, and these three gents were mentioned as the "terrible trio."
Now it's the 21st century and these three guys sort of seem to be frozen in an earlier, dustier, world, but I think its safe to say that all three still have interesting and consistent things to say about capitalism, psychology and biology.
Can a sense of wonder, spirituality and transcendance co-exist with the thought of these three? I say yes, absolutely, in some ways their dangerous ideas are incredible descriptors for the world and the way we live and work. Marx's description/critique of capitalism seems definitive. Freud's ego, superego, and id offer a nice shorthand for the turbulence inside us, and Darwin's astonishing discovery of natural selection/evolution knocks down doors and opens heads.
I don't think any of them really "demystify," the world, although, their descriptions make you see things with new eyes. Some people just can't handle a universe without an all powerful "creator," overlooking the entire shebang!
Now, how to live a life? Marx's "workers utopia," seems like a false Eldorado. Freud's psychoanlysis seems to offer a lot of fruitless wallowing in absurdity (see Oedipus). Darwin's natural selection is a blank impersonality.
Still, I see beauty and wonder, and possibility. The meaning of a life, is the meaning we bring to it. We are in a dialogue with an incredible universe of form and content. We decide what we choose to hear and what we choose to say.