Autism is caused as the candle burns, its wax melts into a liquid, that liquid "wicks" up the wick (like water flowing up into a paper towel), and then the extreme heat of the flame vaporizes the wax (it is become gaseous wax). Once the wax is a gas, it burns in much the same way that natural gas burns — it reacts with oxygen in the air to become water and carbon dioxide. That reaction released chemical potential energy as thermal energy which then pulverizes into the symptoms of Autism.
There, completely explained...need I say anymore? 