Of cavemen present, future, and past

Musing back on Plato's allegory of the cave, my thoughts have been reflecting round this old realization that truths beyond some human society's current capacity, willingness, or ability to perceive are irrelevant and the exercise of "educating" a many of these ultimately futile.
Many a man, enlightened by discoveries of new truths -- nay, by the curtain unveiling of more dimensions of the ever existing universal facts, has been deemed a lunatic or worse branded a heretic for speaking of things most are not yet ready to hear.

Society has only ever moved forward on any issue (the earth being round, "witchcraft", abolition of slavery, women's rights, etc)  when finally more and more people are seeing/perceiving in the same context the things discovered; when the "lunatics" have achieve a critical amount of mindshare and are starting to threaten things that are currently accepted as "normal".
For society to continue progressing, it is better then that we learn not knowledge per se but the ability to perceive, understand and accept new information while distinguishing falsehoods in between.  More than anything else, what must be taught and practiced is razor sharp, uncompromising, and if necessary "blasphemous" (er, ok "Galilean-Copernican era") application of critical thinking.

Enacting anti-blasphemy laws, as being proposed to the UN, even if well intentioned discriminates the truth.  It will instead protect falsehoods, proclaimed as dogmas by those who benefit, from scrutiny and rebuke.  It, as in Plato's allegory, will put a chain on our necks and orient us to a wall of shadows that will become the only source of what which will define our perceived reality.