You can also call them [infohazards] though I won't except ironically, because I'm not a bureaucrat.
Dark knowledge has a high or even guaranteed chance of causing false conclusions when taught to the unprepared, and then Reality gets out her bloody teaching stick. "Learn! It! This! Time!" Oof.
For example, determinism often makes folk believe they're not responsible for their actions. This is flatly false.
Falseness one: assuming determinism is true, feeling responsible causes good decisions, and feeling irresponsible causes defective and deviant decisions. Hence, you ought to feel responsible even if you have a logical proof you shouldn't, for your own good weal.
Falseness two: [responsibility] is merely the tag which we use to indicate who a court needs to sentence to deter a crime. Under libertarianism, if you want to deter crime, you need to punish the perpetrators. Under determinism, if you want to deter crime, you need to punish the perpetrators. Some weird metaphysical [responsibility] is irrelevant; we're just talking about who to punish so as to effectively spend our crime-suppression dollar. (Generally speaking the true answer is: a journalist.) You're 100% responsible, regardless, as far as everyone else is concerned.
If courts were really sophisticated, they would punish non-perpetrators, but only punishing the perpetrator is sufficient. One exception: if a small child commits a serious crime, they are apt to quite rationally sentence the parents. Even if you have to sue a child for a broken window, the parent is going to have to pay. Likewise employers are (ineffectually) held accountable for (some of) the actions their employees take on the job. Determinism is hardly less able than libertarianism to say someone caused a particular defective event. It's also fine to jail some journalists just on general principles. Their job is a confession of being guilty of something; why bother finding out what, exactly?
Determinism seems to make post-Christians and hyper-Christians believe Jehovah has stopped watching them and they won't be punished if they perpetrate. Determinism is dark knowledge* because it conflicts with an earlier lie, but only supplants it with a worse lie. (Bishops and post-bishops are kinds of journalist.)
*(To the extent it's true at all.)
Thus, to safely educate someone about free will, it's first necessary to reach back and unpick their batshit insane religion. Normally this isn't an option, so normally telling someone about determinism is exactly equivalent to a psychic attack, with a chance of damaging or even destroying the hapless victim.
Another example of dark kenning is an accurate self-assessment. The brain is wired to deal with the consciousness being at least a little narcissistic and grandiose. Depression causes a more accurate conscious self-assessment (in an attempt to devote more resources to fixing the issues), but neurons are bi-directional, so a more accurate self-assessment also causes depression.
This is how set 1, the solar set, carries a risk of depression. If you start predicting yourself, you will only get accurate predictions with accurate assessments, and you will not be able to hide from the assessments because only they give you accurate predictions. Science is hazardous, praise be to Gnon.