Btukfyl

In my world, magic is unavoidably unreliable, for example:

You have a puncture. You cast a spell to mend it and with equal probability either it is mended or another tire is punctured.

You are trying to save an injured person. You cast a spell. Either they are saved or you kill them.

Question

It seems to me that such a magic is completely worthless. Can anyone prove me wrong by suggesting a case where both the intended result of a spell and its opposite would both be advantageous?

Note

There is no way to make magic more reliable. It is just a fact.

Sure, it's worth it in many cases.

For instance, if your car is stranded in the middle of the wilderness due to a tire puncture, using magic to try and mend it would be reasonable. In this situation, the car having two punctured tires isn't any worst than if it only has one. You'll still have to make your way to civilisation on foot either way. On the other hand, in the best case scenario (50% chance, so it's not even unlikely) it'll be repaired and you can complete your journey within the comfort of your automobile.

Many similar examples can be thought of in the case of an injured person. Let's say one of your battle compatriots has been injured and you're about the be surrounded by the enemy who you know will show you no mercy. Well, then it makes perfect sense for you to attempt to cure him. Either he will recover and perhaps help your group stand a better chance against your foes, or he will die by magic instead of by the hacking and piercing of steel.

There are all sorts of times where a partly broken object or person is no more useful than a very broken object or person. It's times like these that magic comes in handy.

I suppose this depends if your 'opposite effect' is predictable. In combat you may, for example, try to fireball an enemy, or maybe throw them into the air; you may not necessarily be concerned if they end up frozen or pinned to the ground instead. But you may not want to risk casting the spells if other unpredictable outcomes are possible.

Such a magic would be useful for those situations where you are not too concerned with the immediate outcome but rather the consequences of those actions.

Rough example. There is a war. You don't particulary care who wins but you want the ceaseless fighting and killing to end. So you cast your magic on one side to win. Either they win or they lose...but the war is over! (And if the magic did nothing...try again)

You have to trick the magic into giving you the real end result you want.

If repeated castings are possible, then the odds just got a lot better.

As AngelPray points out:

There are all sorts of times where a partly broken object or person is no more useful than a very broken object or person. It's times like these that magic comes in handy.

The corollary to this is that if you can keep trying repeatedly, and you're not significantly worse off with a failure, you'll eventually succeed. You went from one puncture to two? Cast it again. You have four punctured tires? Cast a spell to repair them all. Your car now has a giant hole in the middle? Cast it again. Eventually, you'll get your car back in perfect condition.

Obviously, this won't work if the "bad" outcome is worse than magic can handle (such as killing your friend, if resurrection is beyond magical means), but in that case, you're back to where we started with AngelPray's quote.

Statistically if you run the spell enough times you would eventually get what you want.

1. So you cast a spell to heal someone, but they die.


2. Then you cast a spell to bring them back to life but their body denigrates.


3. Then you cast a spell to turn their dust into the original person.


4. And so on.

Of course the down side is that each time you fail you may need a better and better spell (and possibly more energy) to fix the accumulated effects of the failed spells. So in the long run those who can cast better spells and who have more stamina have a better chance of getting what they want.

There is also the case of casting a spell that enables you to do something that was already very improbable.

So I cast a spell to print out the lotto numbers on a piece of paper...
There is a 50% chance that It doesn't work out and the paper disintegrates.
Well that's way better than the one in a billion chance I had before.

One of the example, Strait_Jacket treats Unreliable Magic as a kind of pollution.

Due to an invisible contaminant called the "malediction", or simply the "curse", people who use magic too often are at risk in transforming into "Demons," or horrific, malevolent abominations of nature that become immune to ordinary weapons.

This is sustainable as long as the damage comes under control like nuclear power within a reasonable cost. One of the scene, the surgeon having magic overdosed in the operation theatre while using magic like x-ray.

Just imagine you had the magic, today, in our world. Would you use it?

There is your answer.