What does it mean when a person says this must be ...

Hi Vickie.  When someone uses the term "deja vous" it means when they have a specific experience or occurrence, they have a feeling as though it had already happened once before.  People may also feel a sense of "deja vous" when they go somewhere they had never been but once there, they feel like they had already been there...they might even recognize specific things.  Many people experience "deja vous" throughout their lives.  The term originates from the French language and it's translation in English means "again you".

Hope this info helped.

When a person says he feels like a certain event/sight/feeling feels like a deja vous, it means they feel like they have allready been in that event in the past excatly, but they know it didnt really happen. Sometimes, even whole conversations along with the same people and the same place the conversation is happenning in, can feel like it allready happen. This symptom has been investigated so many times before, but no one has figured out the reason it happens. Some psychologists tend to believe that there is a cut in our brain in certain times, and so it is like a computer virus, it just makes us really believed it happened before. Some spiritualists believe that these events happened indeed in our previous life. Others believe that people are born with the entire information about their lifes, and anything that happens in ones life, is allready known to our brain. But it is placed in our subconcious. Sometimes, as said before, there is a cut in our brain, and some of the information slips out. In french the correct translation is 'seen before', as in something that has been seen allready, but you cannot tell where, when and how.

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It says in short: "It is familier to me from previous experience" (that is exactly what the French expression says.