Global Warming Deniers Difficult to Understand

   I have recently been in more debate about Global Warming.  I am amazed by the sheer ignorance of fact displayed by the Flat-Earthers who refuse to believe basic, easily observable fact.  I actually heard one person assert that Mt. Pinatubo put out more CO2 than  all human activity has.  A simple fact check shows that the CO2 output of Mt Pinatubo was 1/700th of the current annual anthropogenic CO2 output.
   The same person also argued that the people (most of the civilized world!) who warn against global warming somehow make a profit off it.  In fact, the money interests are the ones who advocate for continuing to pollute this planet's atmosphere. Even many of those people have (particularly in petroleum interests) begun to move toward renewable energy programs.  Only the Coal industry has failed to move in that direction.
   One interesting fact about the effect of volcanic eruptions on weather is the apparent link between an eruption of Krakatoa about 535 AD which seems to have caused such global cooling that it precipitated the Dark ages.  I suggest that you do a quick internet search if you want to find more information about that. Volcanoes may have emitted large quantities of CO2 billions of years ago, but that has not been the case for a very long time.
   I have also heard an argument that seems to say that climate scientists use a computer program (number crunching) which agrees with observed fact, therefore both are wrong.  Talk about the faults of rationalism!.Please, if any one has a different interprettion of the problem with having theoretical models which agree with fact, explain it to  me!