@Diogenesister, this is how I understood it (I rephrased it):
"But the stunted psychology of those raised in extreme
religion is another problem altogether. For these children, there is no
obvious lack of common sense or ignorance of life's ups and downs that we all experience in our journey to adulthood. Rather, they experience a totalizing
indoctrination that so severely limits the formation of an adult
psychology that many don’t ever achieve maturity in the way secular
society conceives of it, a state of empowered capability that permits
complex life choices, a state in which contradictory ideas can be held
in tension without psychic recoil. Instead, the fundamentalist child,
raised on fear and limitation, lives a life of diminished options,
constrained by strict dualisms: black and white, good and bad, God and
Satan, and (perhaps most alarmingly for the broader culture) us and
them."
The point I got from that sentence and the one about "maturity in the way secular
society conceives of it", is that people indoctrinated in fundamentalist Christianity and other cults and extreme religions may appear to be pretty normal on the surface. Most adults appear to have some measure of common sense. Most adults have faced the harsh realities of life such as sickness and death. They appear to be able to handle such things with a measure of maturity and rationality, but that's where it stops for cult members. Growing up I always thought that the elders were the most brilliant men walking the earth. I thought I would grow up and be just like them. Then I found out TTATT, and realized that not only are the elders complete idiots, but that I'm one too. I'm still undoing the damage.
Sure the elders and other cult members have an appearance of intelligence, but let an elder catch you watching a scary movie. I was told by an elder that watching certain movies or listening to certain music would subject me to demonic attack. He then told me that if that ever happens, make sure the lights are on and say Jehovah's name out loud. I've been told that cigarettes would have the same effect, and that smoking is just like practicing spiritism. I grew up listening to Local Needs talks about pornography at least once every two or three months, but not a single one of those talks ever addressed pedophilia. I grew up asking elders for advice on how to make a living, and was told not to be concerned with such things because Armageddon would come soon. I even asked one elder about his job, and he told me not to get too involved in Satan's world. I wanted to say, "If your job is so bad and so wrapped up in Satan's world, why do you do it? Why don't you just quit?" But of course I didn't do that. I just dropped the subject like the brainwashed idiot that I was. Fundamentalist Christianity takes people that have so much potential, so much personality, so much to offer the world, and turns them into a bunch of superstitious morons.
Let's review: It's a cult!!! (I've always wanted to do that.)