I wrote this up and put it on Discord, but just for anyone who maybe hasn't got Discord, etc., I thought I'd post it again here. Certainly, it's open for discussion, interpretation, etc.
So, I've had this theory about why wizards live so much longer than muggles. For example, Rowling said Dumbledore was approximately 150. I think it may also explain a little about why there are squibs and why most muggles can't do magic and why wizarding medicine tends to be so different. I don't know it this makes sense but I'm just gonna put this out here and see what you guys think.
I honestly think that wizards probably are biologically just a wee bit different. I think that while all humans have a number of bodily systems (nerve, digestive, skeletal, etc.,) I think wizards might very well have an additional bodily system that most muggles do not. I think they have a magical system that looks and functions very much like a secondary nerve system. The nerve system in humans is an electrical system, and i think the magical system is an electrical system too.
I think, first of all, it explains the longevity of wizards, very much like, if you have a flashlight with one battery, it generally tends to run out quicker than a flashlight with two batteries. It also, I think, explains why certain spells create a huge energy drain on the caster--like when Remus gave Harry chocolate after practicing the patronus spell.
I think it also explains why a spell's effectiveness depends upon the intent of the caster, (ie, "You have to mean it, Harry"). And, i think it explains why a wizard can cast nonverbal spells as well as wandless magic spells, and why Harry was accidently casting magical spells before he had any idea he was a wizard. And, one more thing,
I think its important that there is a huge difference between muggle medicine and wizard medicine. Muggle medicine often relies not just on medicine but also on invasive procedures that sometimes cause pain and wounds and long healing time, and can tax and stress the human body in massive ways in the effort to make someone better in the long run. Wizarding medicine relies primarily on potions and spells and is almost completely noninvasive. That would put far, far less stress on the wizarding body that, when combined with the different biology, should, theoretically, extend the life of a wizard significantly more than their muggle counterparts.
It would apparently mean that wands are basically amplifiers for the wizard's magical ability and also explains why the wand chooses the wizard. the wand seems to be created with a certain ability to maybe work a little like a magnet and it is drawn to a caster who's magical system will properly align with the different woods and cores that are placed in the wands. You see what my brain does when its left unsupervised very long? rofl
Now, have I managed to confused the daylights out of everybody?
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