This is something I’ve been having some doubt about, ever since a friend of mine said he considered such a thing to be quite shallow. Can you actually say things like: he’s a narcissist, she’s egotistical, they’re smart and so on? I mean, surely you can do it after getting to know a person, but can you say that someone is a narcissist only by the fact that they like to wear tight and revealing clothing? Can you say that someone is dominant or extroverted or self-confident by the strength of their handshake?
I don’t know. I don’t like not knowing.
What you most certainly can do is make comments on their behavior and behavioral residue. If there is a lot of mud on the shoes, that person has obviously been outside. If one’s clothing is dry and clean, and it’s raining outside, one can safely infer that the person has either been indoors the whole time or has changed attire.
But what about their personality?
We do not like to be negatively categorized, even though we fully embrace positive categorization. No one likes to be called lazy or selfish, but rarely will you find a person refusing to be called trustworthy or steadfast. So if I as an observer decide to call someone vain or untrustworthy, there would be a lot of disproving. If I were to call someone altruistic and creative, my words would be accepted. This still tells us nothing about the veracity of the personality inferring process.
If you call people bad things based on what you see, you should at least be able to call them good things based on what you see. I think this question is a matter of preference and opinion, not of fact. Some people would avoid personality deductions altogether. This is fine, but I feel you lose a lot of information out of fear of being shallow or mistaken.
So my working solution for this problem is yes. Yes, you may judge people’s personality from what you perceive. But, as in other deductions, change your deduction if new data points to another direction and do not suppose more than what the data tells you. If someone is selfish, it does not necessarily mean that the person is also a liar, nor does it mean that being selfish increases the chance of that person being a liar, or anything else, for that matter. If you conclude that someone is selfish, well, then it’s the only thing you conclude.
I do not guess. I observe. And once I’ve observed, I deduce.