I thought this was very interesting.
I am not sure how much I believe in the theory below, but certain eye ‘expressions’ are terrifying – particularly wide staring eyes. I have seen it happen over the years in people who suffer from heavy drug addiction and/or serious mental disorders, and it is terrifying. It is usually accompanied by ranting or shouting. Whenever it happens near me – in public spaces or public transport – my body goes into full alert. I always wonder why humans instinctively react to certain body language or facial expressions, interpreting them as a threat. I assumed it was something in our lizard brain reacting to a perceived threat.
Sanpaku refers to the whites of the eye being visible on three sides. In Japanese physiognomy (or face reading), whites above the eyes denote a dangerous or violent personality (as exemplified by Charles Manson).
In western terms, sanpaku is called “scleral show” and may simply be a function of genetics, endocrine issues, aging, or surgeries like blepharoplasties.
However, seeing the whites of someone’s eyes, combined with a cold hard stare, will give you chills. It’s called a reptilian gaze. Such stares activate your limbic system, causing you to go on alert.

That explains a lot about Charles Manson and my most recent 2 exes. They both had whites visible at the top of their eyes and I should have been aware of this and never got involved with either of them.
This is so interesting! I didn’t know about that. Charles Manson has always been really scary for so many reasons but staring at the picture you shared definitely hit it on the nail. I am lucky to never have met people who had those eyes and I hope it stays that way!…