It’s not about inability to understand, mind, it’s about unwillingness to understand.
There are plenty of people who have mental deficiencies who are well aware of that, and how much trouble they have understanding the world around them. But they at least try.
The same can not be said for those who are perfectly capable of understanding, yet simply choose not to.
I have a quote that fits this situation well:
It’s not about inability to understand, mind, it’s about unwillingness to understand.
There are plenty of people who have mental deficiencies who are well aware of that, and how much trouble they have understanding the world around them. But they at least try.
The same can not be said for those who are perfectly capable of understanding, yet simply choose not to.