I have a secret to confess: 90% of the books I read are fantasy. I can hear it now: “But you always stress the importance of scientific accuracy. Magic isn’t real.”
I know, I know, but I still hold fantasy to the same standards as sci-fi. While magic will never be scientifically plausible, it must still operate logically, with rules and limitations. The only difference between these genres is that the author defines the laws, not a scientist. But once defined, those laws should not be broken. Magic without limitations is just as bothersome to me as inaccurately portrayed science. A wizard who can make an obstacle disappear with a wave of his wand is no different than a star-ship captain who uses a fancy DHTMB (doohickey-thingamabob) to vaporize an obstacle.

I enjoy fantasy for the same reason as everyone else, to be taken out of our world and go on a narrated tour of the fantastical. But magic should still have logical consistency, otherwise it’s impossible for me to get fully immersed in the story. Don’t get me wrong, I can still enjoy fantasy books without a strict magical system, but my enjoyment is of other things like the characters, the setting, and the writing style. In those books, I am indifferent to the magic; it doesn’t add anything for me. If all you need is a magic word and a wand to solve all your problems, I might be envious, but I won’t relate to the story. Writers that create a magical system complete with strengths and weaknesses, and explain what is possible and what is not, immerse me in the story much more effectively. In order to pretend magic is real, I must first understand it.

I am a huge fan of Brandon Sanderson, largely because of his originality, but also because of his firm grasp on what makes magic enjoyable and captivating. He has created a set of laws that can help writers create a believable magical system:

Magic is defined as soft or hard magic in Sanderson’s first law. This is much like soft or hard sci-fi. Soft magic does not follow any set of laws and can’t easily be predicted. It is mysterious and capable of almost anything. Hard magic is well-defined, and has logical limitations. I tend to think of soft magic as a background feature in a character driven story, something the author uses to nudge them in a certain direction or patch up any holes in the plot (my words, not Sanderson’s). Hard magic is integral to plot and setting, something the main character must understand and use wisely in order to overcome obstacles. Neither have to follow the laws of science, but one is more defined than the other.

The second law is a law of limitations, where magic has weaknesses and strengths, i.e. there should be a cost to using such power. By Sanderson’s estimation, the best magical systems have more limitations than power. This is another way to make a magical system logical, for there is no such thing as action without consequence, and no such thing as infinite power.

Another way to infuse logic into a magical system is to follow Sanderson’s third law. Sanderson tells us to think through the consequences of the magic we have created, to try to think of how it will affect the world. If everyone has the ability to fly, I’m pretty sure they won’t be driving cars to work in the morning, or waiting around in airports. If everyone lives forever, there will probably be strict rules on procreation to prevent overpopulation. There is nothing more jarring to a reader than a contradiction. Making the laws simple will also help limit confusion, and keep it from becoming a tangled mess.

Logical magical systems are something I have been striving to create in my own writing. The magic in Agony’s Fire is very simple, but it can be used in countless ways. It is based on a single premise, that in a place devoid of time, space, and matter, there is nothing to stop anything from coming into being. In this place, a simple possibility can make it a reality. However, nothing made in this Void can enter our reality unless it follows all of its laws. Therefore, the user must have a perfect understanding of what he/she is trying to create in order to bring it into existence. Because the human brain is so limited, my characters have only managed to create the simplest form of energy: heat. So far. But heat can’t be created from nothing. The energy used to create fire is pulled from the mind of the user, where the possibility and understanding of fire originated. Likewise, you can pull energy from the world into the Void, and to balance that loss, the energy is placed back into the individual’s mind. It is a magic that can be used in many creative ways, but one that is also limiting. They can heighten their emotions, senses, cognition (which I term the Agonies and Sanities) when drawing energy from the world to create cold, or they can give some of it up to create fire, hence the title Agony’s fire. Pull in too much energy from the world and they can have a seizure, but give too much energy to the world and they can lose consciousness, or worse, their sanity. This magic has also created a society of people who wish to learn, for only in understanding something completely will they be able to create it.

I would encourage you all to write down the laws of your magic and summarize them like I just did. If they are noticeably fickle laws, and they fall into the realm of soft magic, then perhaps there is a way to strengthen them. Sanderson’s laws are a great template to start from. But the logical consistency of magic and science is just a small part of what readers are looking for in a book, so if it becomes too monumental a task, make sure to focus your energies on good writing, powerful plots, and believable characters.