Maggie Koerth-Baker differentiates between "little lowercase 'theories' and uppercase 'Theories.'” She argues that scientists in the 1970s discovered the big Theory of climate change was true by disproving the smaller theory of global cooling:
Scientific theories are frequently overturned by new evidence. But, just as often, the new evidence changes one part of a theory, while leaving the big picture intact. That’s because scientists use the same word–”theory”–to describe two very distinct classes of ideas. Gravity is a theory. But so is the existence of Gliese 581g–a wobble in the light given off by a distant star which may, or may not, turn out to be a planet. One of these things is not like the other. Of the two, new evidence is much more likely to disprove the existence of Gliese 581g.
On a separate note, Marcelo Gleiser is comforted by the spirituality he's found in science:
I find solace in how modern science places us within the cosmos: the materials that make us and our planet came from the same stars; the time that we depend upon so much to quantify change is a measure of the expansive universe itself. We are, in a very direct sense, products of the comic history. We are, now and here, a living and thinking conglomerate of trillions and trillions of atoms, condensations of energy that will flow away one day. As John Muir wrote, "When one tugs at a single thing in nature, he finds it attached to the rest of the world."
The Dish 