Why?

Why can't I remember peoples names? This has never given me a major problem until now. I could carry on a conversation for hours without knowing the person's name. I met a good old friend at a gathering today. It was such a surprised because the last time, I talked to him it was 7 years ago, when we were in 3rd or 4th semester and he was moving to the main campus. He was just one of the few people that I clicked with the first time we met. You know how suddenly we could hang out with people whom had similar interest with us. So I considered him one of my closest friends during my diploma. So far I kept in contact with most of my friends. However I KNOW THEIR NAMES !!!!! So its easy to find them on various social networks. Argh!!!!!! Tension!
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