How do you know if someone has schizophrenia?

what are the signs?

Schizophrenia can be hard to recognize at first and is often confused for multiple personality disorder. They are not the same. Schizophrenia is a biological (i.e. physical rather than emotional) condition, therefore it can be diagnosed and treated by a physician. The most common warning signs are obsessive compulsions and frequent mood swings which span from extreme highs to extreme lows and back again.

I don't have schizophrenia but I do!
If you ask someone a question & they both give you different answers.
Going out and buying presents for your self!!!
depends wich one of them you ask
They hear voices talking to them. The voice is outside their head (important distinction). The will often talk back to the voice. They may think the TV etc is talking to them.
Some people only care to joke about questions, apparently. Oh well...

Schizophrenia is difficult to recognize, especially since the people suffering from it are usually totally unaware of it. One indication might be if people show completely different personalities (like one day extremely precise, the next completely disorganized).

I think I read somewhere, though, that they have found a way to recognize schizophrenia in a brain scan. Just can't for the life of me remember where.