That's also true of a fire, the light from a lamp, or any other form of energy, or matter. The energy from the fire goes somewere else, as a different form of energy. That doesn't mean it's still a fire when it does so.
That is absolutely true, and that is the nature of all things scientific. On the other hand religious sources have claimed since the beginning of religious writing to know absolutely that there is a soul that is separate from the body, all without any evidence other than the claim that it is so.
It's easy to dismiss science for not having a particular answer, but claiming the existence of something because science can't disprove it borders on deception in the sleight-of-hand category. Science can't disprove the existence of a separate concsiousness, or soul. Science can't disprove the existence of God. Science also can't disprove the existence of Bertrand Russel's Cosmic Teapot, or, as I like to say, the existence of little blue bug-eyed men from Atlantis living in the oceans.
http://en.wikipedia.org/wiki/Russell's_teapot
To summarize: Science has shown that energy changes form, but does not cease to exist. Science has also show that energy and matter are interchangeable, so that combining oxygen and certain materiels and applying an external energy source can cause combustion. Science has further shown that the matter consumed in the combustion takes on a different form of matter or energy.
What science has not shown is that any given part of the matter or energy continues on in the same state, or at least enough to support the claim that the matter or energy will continue to exist in the same state for all eternity. No, there is no proof that the consciousness or soul cannot continue on after death, but there is no reason at all to believe it will other than the desire for it to be so. Do people believe this because religious writings claim that God has revealed this to certain people and they wrote it down, or was it written down because people wanted to believe it?
I don't claim to have an answer, but those who do claim to have an answer don't believe in the existence of certain concepts
because those concepts can't be disproven. They use the fact that they can't be disproven to support their beliefs. That is about as unscientific as one can get, not to mention unreasonable and irrational. And, to me anyway, a little dishonest.