They used to shoot messengers.
I thought it was when they brought bad news, but that wasn't it. It was to stop bad news from spreading.
We have a societal impulse to suppress: for reasons of politics, religion, culture or preference. The challenges to free expression come from many directions - maybe we find your politics distasteful, or perhaps we believe the conspiracy you're peddling has the power to kill.
There are causes that unite us - we have, for instance, the means to develop hybrid humans, but don't pursue the science. Similar ethical arguments could rally a jihad against AI.
But such approaches rarely end well. Suppressed information is shiny; the Streisand effect exists because we all want to know the gossip. And you can't crush knowledge, only send it downwards; like the illicit literature of the Eastern Bloc, it'll thrive underground. If you won't let us watch it, we'll VPN or torrent it.
Calls for censorship grind against our desires for knowledge to be free. Only a truly totalitarian state can control minds; in reality, we tend to forget important truths more through carelessness than malice.
A friend pointed out that some forms of knowledge are mystical, others elusive. Marketing is mystical: chock-full of bullshit and pseudoscience that obscures true signal. Other worlds are elusive, like the closed-room VC deals known only to the initiated.
So knowing is often more about discernment than secrecy. As Edward Snowden explained, conspiracies are all around us, in the open. His friends in intelligence would agree - most spy work is interpretation, based on open source intelligence from the public domain.
Knowledge of the self is similar. Therapy is a process of realisation, of discovery; a mirror to the realities you're blind to. Just as my years spent as a devout Muslim meant living numb to contradictions, like the fact that 'there's no compulsion in religion' - but apostates must die.
You just don't see it til you see it.
It's not new information, just new framing.
The truth is usually staring you in the face.