Why does the Dude block people who can answer his questions.?

Why is the Dude blocking people with scientific knowledge about how the WTC collapsed? He's talking about molten steel again, but the WTC did not need to melt to collapse, the properties of steel are altered by heat befor it melts. 'molten steel' flowing from the fire could of course have been many other substances, such as aluminium and is now thought to be due to a set of batteries that were ignited.