Look outside the box only after you've looked inside it
They do break rules, but not because they can. They do it when there is a problem which requires something new, an answer that can't be found inside the box. That's when creativity is called upon. Beginners tend to be attracted by the unexplored because they want to innovate, do something that has never been done before. That or they want to create an identity for themselves by striving to be unique. Mark points out the problems with this. First, you are breaking conventions and making things that don't work the same. Second, you are using up design space that could had been saved otherwise. Third, you lose coherence and cohesion because you make something that doesn't fit with the rest of the pieces.
By sticking to the rules first you avoid all the above. The cards maintain coherence and cohesion and less design space is used unnecessarily. Mark likes to explore the unexplored because that feels natural for him. This urge to go in newer directions is good, but at the same time he has to be cautions because their first goal is solve some problem and not create new problems. Often times what is different is not better.
What he says is rooted in cognitive bias. When we are presented with a problem, our first instinct is to look for something familiar. We ask ourselves "Have I ever solved a similar problem before?". That's how learning mathematics works. Mathematics and science in general require tools and the more experienced we are, the better we can do. Science is a cumulative process where tools get better over time. The same could be said about Mark and designing magic. Over time they gained more and more experience. By reading Mark's articles and columns one thing became clear: most cards were influenced by older cards in a way or another. He's pretty right in stating that over time design space tends to become narrower as there isn't an infinite space to it.
What he said about beginners wanting to be brave and pave new paths which have never been tried before applies to science as well. At college / university it's common for freshman to feel that they are above average and this is reinforced by grades at school, parents, relatives, competitions, olympiads and by being accepted there first of all. I saw it happen first hand. Admission exams can be though and most of the time they are. Then comes an exam and the grades of your peers are above you or you feel disappointed by your own grade, no matter if it was quite good. Sometimes people feel as if they are the next Nobel prize winner or the next genius who is going to solve a problem which has remained unsolved for many centuries.
In the case of unsolved problems in science it's very unlikely that some genius is going to solve them in a short amount of time. Even if somebody does, the solution didn't came out of nowhere. Taking mathematics as an example, everyone has to learn the most fundamental tools first, else it's impossible to make any progress. This is something that I've learnt with physics and mathematics. Unless you master the basic algebra, trigonometry, Newton's laws, you can't expect to solve any complex problem. There are some basic tools that are required first and without them any complex problem is going to be a nightmare to solve. Every complex problem can be seen as many smaller problems tied together and I'm pretty sure that Mark sees Magic the same way.
I've read an interesting paper once in which physics students failed to solve simple problems, while doing quite well on complex ones. How is that possible? There is some sort of bias in which we believe that something is much more complex than it really is in reality. There are some math puzzles which rely on this fact and the solution is something that most people miss. There is a problem called "The Amazon's hanging cable interview question" which can be solved by simple observation, yet it's presented in such a way that most people are fooled to think that they require a series of complex calculations to solve it. This pretty much relates to Mark's own lesson "The right answer is not always apparent first".
I think there is something about being humble here, because we often feel above average because we can solve complex problems and yet, fail to solve much simpler ones. I once studied math the wrong way, focusing on complex problems first. Most of the time this approach is a failure because you spend so much time in trying to solve something that you can't, that you forget about learning the fundamentals first. This is very much trying to find the answer outside the box first, not inside it. To put into other words: sometimes the answer is much closer to us than we really think it is. I could even see how this applies to psychology as well. Because there is one valuable advice from reading about toxic relationships. Toxic people are toxic because they have their internal worlds in turmoil. You can't bring peace if you are at war inside yourself.
To cite an example about level design and game design. Most of the time people want to do something completely different. They want a level or a game that is groundbreaking. I lost count of how many times I attempted to build a level which was beyond my capabilities. This closely relates to what Mark said and what I said about college. If I can't build the most simple level of a game, how can I expect to build grandiose levels? The same applies to programming games. The fundamentals always come first. I could say that if there is someone obsessed with being different, unique, to stand out, there must be some mental disorder in play.
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