Neo's "dead"

Rating: 10/10 (6 November 2003)

That's something that left me confuse. If Neo gets transformed on Smith, how and why does Smith "explode". I already realized that if Smith was created thanks to Neo and it's his exact opposite, if Neo dies so does he( but this is only a logical deduction and a cause/effect reaction there are no other reasons for this to happen", i just don't realize how and why! Can someone explain that to me.