Daniel Dennett is an American philosopher, who has (amongst others) tried to look at evolution of religious ideas through the lens of biology. Read his bio at TED.com here.
Here he talks about spread of Dangerous Memes.
A meme (pronounced /miːm/ - like theme) comprises a unit or element of cultural ideas, symbols or practices; such units or elements transmit from one mind to another through speech, gestures, rituals, or other imitable phenomena. The etymology of the term relates to the Greek word mimema for mimic. Memes act as cultural analogues to genes in that they self-replicate and respond to selective pressures.
Here Prof. Dennett is talking about spread of toxic memes for things like Pornography and other ideas (like Fundamentalism).
This is very valuable for us to understand if we need to fight and win the battle. The battle for creating a Hindu Rashtra is essentially a battle for minds and thoughts and ideas.
Listen to this thought provoking lecture by Prof. Dennett.
Where Prof. Dennett warns us about being careful about spread of ideas and technologies, I was wondering how Manu Smriti is saying something similar. Essentially that access to powerful ideas and technologies is not for everybody.
And the criteria is not birth or caste or whatever. It is being सुपात्र (eligible - the right candidate). So Gurus refuse to teach critical mantra to their own sons if they do not find them eligible. The prefer to let the technology / idea die than to allow it to proliferate and cause damage to the society.