Show Me Your Wallet, I'll Show You Your Soul
You can tell a lot about a man by where he spends his money. It feels strange at first. Counterintuitive too. Money has become the clearest expression of our personality. A lack of money makes us desperate. An abundance of money can make us arrogant. Our treatment of people differs by how much money they have. Your influence depends on how much money you have in the bank.
Our reputation hinges on money. We are judged by how much we earn. Heck, if you are a man, you will be loved in proportion to how much money you manage to make. You will not be loved if you don't make much. You will be labelled a failure solely on the basis of your paychecks. So naturally, money governs our entire life. I don't mean to preach, but money is basically how we experience life.
A man who grew up poor spends on things that signal he is no longer poor. Especially the one who has been mocked for his poverty. Observe closely and you can tell that he despises that poverty. He can empathise with the poor, but he no longer wants to be part of that phase. He is attached to his money because it makes him feel better. You can tell that he spends not out of taste but out of the disgust he feels for his past.
There are people who remain middle class in mindset no matter how much they earn. They are always hoarding money. Saving for the bad times. Always thinking and planning for the bad times. In that thinking and planning, they completely forget that the good times have already passed them by. The classification of time is a mental construct. You lose out on your best years hoarding something that is only useful during your best years.
Observe closely their spending habits. Do they spend on partying? Do they spend on gifts for other people? Do they spend to please people by being extravagant? You are looking at a potential people pleaser. People pleasing is misery dressed up as niceness. It's a mental affliction.
Once you start noticing these patterns, you will find them everywhere. Even within yourself. Ask yourself why you spend where you spend. Everybody knows that women love to shop. Especially when they are feeling down. Women feel happy based on how beautiful they look and how beautiful they feel. Shopping for new outfits, new shoes, new accessories makes them feel beautiful. Makes them feel better about themselves, at least in the mirror.
If you are curious about someone's personality, conduct a simple observation for a few days. Notice their relationship with money. Because money is the clearest expression of self. Even if they share nothing about themselves, their spending habits will reveal everything.