I first encountered the word "physiognomy" in "Wuthering Heights". It is surprising that Emily Bronte was aware of the term and was able to examine it through her fiction. Lord knows how she herself met the word for she lived a sheltered life in the Yorkshire vicarage at Haworth, next to St Michael and All Angels' Church where her father was the incumbent vicar.
What does "physigonomy" mean? It is simply the idea that we can make out someone's inner character or state of mind by observing their facial appearance. It's as if the two are inseparable - what is on the outside and what is on the inside. The belief runs counter to King Duncan's observation in "Macbeth": "There's no art to find the mind's construction in the face."
I think that we are all liable to put too much store in physiognomy and I am no different from anyone else. Perhaps it is human nature to start assessing other human beings as soon as we see them. Typically, we will initially think warmly of smiley fair-haired people with wide blue eyes. Conversely, we will be apprehensive about scowling dark-haired people with the corners of their mouths turned down.
In my life there have been many times when initial assessments have had to be thoroughly revised. That woman you thought was a miserable, depressive soul may turn out to be a happy-go-lucky joker with a heart of gold. Similarly that very together guy, apparently living happily on an even keel may turn out to be dark and suicidal. Things are not always as they seem.
Judgements based on physical appearance are invariably superficial and misleading. We should be wary. "Physiognomy" is a clever-sounding concept but in reality we should not put too much store in it. There is usually much more to other people than first meets the eye and in the end I subscribe to King Duncan's view.