So I've had this question in my head for the past few days, and I thought maybe you could help or something.
There are two theories about the universe I can imagine.
1. The universe is finite. This means that there is a set amount of matter in the universe and all of it is being used at all times. When something is created, something else must be destroyed to keep the balance. Assuming magic exists, if someone used magic to save a life, another must die. This is also assuming that magic exists outside of fate, so the person who was about to die, wasn't Meant to be saved, and it caused the disruption in the balance that required an equal and opposite unplanned death.
I'm trying to stick to the laws of physics as much as possible here, bear with me.
2. The universe is infinite. This would mean that there is no set amount of matter in the universe and therefore not all of it can be used at all times. When something is created, an equal and opposite effect is not required to maintain balance. Continuing with our previous assumptions, if someone uses magic to save a life, that is all that happens. Another is not required to die.
In Merlin, we are told that for one life to be given, another must be taken. But then who's life is taken all those times that Merlin saves Arthur from various creatures and afflictions?
If we say that Arthur was meant to be saved by Merlin's magic, that would mean that Magic exists within fate and then there is no reason for Arthur's mother to have died when he was saved. UNLESS. The thing that makes Merlin the most powerful sorcerer on Earth is the very fact that his magic alone exists outside of fate.
Think about it, all those time that Arthur was meant to die, yet Merlin saved him. And when he tried to bargain for lives and kept losing them from other people, when he'd meant it to be him, he chose who would die to give them life. Not even Nimua could do that, though she liked to pretend she could.
The question remains; Which universe do they live in, finite or infinite?
