Eric Falkenstein, referenced recently by Robin Hanson, and at other times by Isegoria, had a long discussion about science.
Roughly, Science is complicated, and anyone (esp. non-scientists) saying "the consensus is" is mostly trying to shut off debate, and should be ignored. See AGW (attempts to shout down dissent), and Falkenstein's links to astronomy's attempts to explain planetary oddnesses are an asteroid's worth of riot.
So...next time someone says...Econ isn't a science, or Consensus is....think about this article. Also good for post-modern anti-science rhetoric.