What happens to a candle flame when you use it to light another candle? Look at the flame when you do it. Rashi says it will not lose anything by doing this, i.e. its own flame will not be diminished.
Not only does a flame not lose anything by lighting another light, it gets even brighter when it is standing together with the new light. Try it and see. Go help a fellow Jew to put on tefillin, or show a Jewish girl how to light Shabbos candles and see what happens to your light.