[adityab]

You raise a good point. My answer is:

I understand the idea of doing probablistic inference about people based on their demeanor. We do it all the time with our minds, indeed many aspects of society and culture are built around non-verbal communication.

I'm okay with how things currently are, because we are innately capable of learning behavior policies for social interactions, while preserving a lot of cognitive privacy. In other terms, you can consciously control your demeanor (as the word is currently understood).

I afraid of inferences drawn from sub-conscious demeanors and involuntary information leaks.

Normal humans will not be able to tell if someone is nervous or afraid or angry just by looking at them, if that someone wants to maintain a pokerface. But it is entirely possible to read someone's pulse by recording a video of their skin, thus taking away some privacy of the mind [1].

We haemorrhage a lot of information all the time. As far as I know, current polygraph tests are trash, but I would be unsurprised if some characteristic features were to be found in a video+audio stream of someone's face that would estimate with good accuracy and precision that they were lying.

We all lie. To others and to ourselves. Within limits, lying is an integral part of healthy life. A world where I cannot casually lie is not one where I can live in; cognitive privacy is important.

[1]: http://people.csail.mit.edu/mrub/vidmag/