Why are people afraid to ask

It has always puzzled me why people, even so-to-speak rational people, are afraid to ask or even think some things. It's something I keep finding in front of me all the time. I'm not talking about uneducated people, I'm not talking about religious fundamentalists. I'm talking about so-to-speak scientists, engineers, doctors.

It occurred to me, again, today, to consider the question. I was attending a conference and, during a break, there was a discussion about class hours. It was mentioned that in some university in the US they used to schedule all classes for 80-minute long periods and that this posed problems with scheduling and keeping regular time tables. Be it as it may, the conversation was turned into how to divide the 60 minutes of an hour into smaller intervals. I mentioned that, unfortunately, we are still stuck with the system created by the Babylonians who introduced the sexagesimal system in artithmetic. (That is, they counted using base 60, instead of 10. So, for instance, they had to learn multiplication tables which were of size 60*61/2=1830, instead of 10*11/2=55. They had good reasons for doing so, for 60 has a large number of divisors: 2,3,4,5,6,10,12,15,20,30.)

The interlocutors were puzzled: "what are you talking about"?

I explained that we are stuck with a non-decimal system of counting time and angles precisely because of this historical accident. It would be nice, I maintained, if at some point we changed it.

Their reaction was that this is impossible. To them, who probably never thought of even considering the question, it was impossible because it has always been so.

I explained that there was nothing fundamental with it and so it could be changed, if there was some kind of agreement. After all, it's a unit of measurement, just like miles and kilometers. It was interesting to observe, again, that they were willing to accept that, albeit difficult to change, it is not impossible. I asked them to consider the difference between a convention (such as the choice of a unit) and a fact, such as Newton's law-at low speeds, the rotation of the Earth around itself and the Sun (I mentioned that there are some stupid people who think that the Earth is still) or the principles of General Relativity. One of the conference participants claimed  that the latter makes absolutely no difference in practice. At which point I reminded them that the Global Positioning System (GPS) does take into account relativistic corrections.

The conversation proceeded to talking about the difference between a convention and a fact. And I realized, once again, that the two concepts are confusing for many people.

Therefore, it is not surprising that, when fundamentalists with rhetoric abilities appear, they can attract lots of followers and create cults. Or that politicians can do whatever they want for their own benefit.

People impose boundaries to themselves by not allowing themselves think freely, by imposing limitations on their thinking process, by enslaving themselves.
For many humans, the Enlightenment did not exist. It's irrelevant. Alas, despite Kant's message, Sapere Aude (have courage to use your own reason) there still are many who, not only cannot think freely, but won't even consider the possibility that their thinking is accompanied by heavy chains.