I heard about the Dunning-Kruger Effect about a month ago. Now reading about it, I had no idea it was such a recent discovery. It seems like it would be fairly obvious. But of course, the fact that it seems fairly obvious to me now is exactly the Dunning-Kruger effect. It seems obvious because I now know it. Before I knew what the Dunning-Kruger Effect was it wasn't obvious because I didn't know that I didn't know it existed.
How could you properly self-examine if your initial inference is that your hypothesis is correct?
I realized when I was a student that if I have the wrong method I could do the same problem over and over and come up with the same result. The consistency of results would lead me to believe I was solving the problem correctly. However, my consistency was merely consistency in failure until I was taught the proper method.
Until someone is shown that they are wrong they are highly unlikely to suspect they are wrong. We've used all of our evaluation tools to formulate our original hypothesis, it seems ridiculous to believe we could use the same tools to find out where our hypothesis is wrong. Using the same faulty tools will give us the same faulty response.
Ignorance is really just ignorance and should not be demeaned. However, refusal to learn is an abomination and should be loathed.