A nice piece on the scientific mindset by Andrew Pontzen
Once we admit that we really do operate in this world of personal belief, what makes us "scientific"? Essentially that we never assign any statement 100 per cent confidence (which would make it unassailable). We try to hold beliefs that can, given enough evidence, be overridden.
This is what we all ought to aspire, but let's face it we all fail to one extent or the other. This is okay, but at least one ought to try damn hard at it.
A cheap con that is all too effective as pointed out by Shawn Lawrence Otto.
One of the most common tactics deniers use is something I call The Impressive Letter Technique, or this being NASA, let it be known by the acronym TILT - which is exactly what it tries to do to your thinking. A TILT is a letter signed by a lot of impressive sounding people who make a public statement or demand, and expect the gullible antiscience press (whose last science class was probably in high school), and the public, to lap it up because of their collective authority.
What gets me about letters signed by "NASA Employees" or "Scientists" is that who cares what most scientist opine on a topic not within their field of study. If the ophthalmologist says that I should not wear contacts for whatever reason, but the Nurse Practitioner thinks that contacts are just fine, and hints that all ophthalmologist are in cahoots with "big spectacles,"whose advice do you follow? The expert or the lessor train professional with a conspiracy bent? Yet, it is an cheap effective technique.