evidence: Global Warming: How Do Scientists Know They're Not Wrong? [...] Contrary to popular parlance, science can never truly "prove" a theory. Science simply arrives at the best explanation of how the world works. Global warming can no more be "proven" than the theory of continental drift, the theory of evolution or the concept that germs carry diseases. [...] One argument commonly used to cast doubt on the idea of global warming is the supposed predictions of an impending ice age by scientists in the 1970s. One might say: First the Earth was supposed to be getting colder; now scientists say it’s getting hotter—how can we trust scientists if they’re predictions are so wishy-washy?