KenKen Puzzle Inventor’s Tips for Engineers to Think “Outside the Box”

KenKen Puzzle Inventor’s Tips for Engineers to Think “Outside the Box”

Mr. Tetsuya Miyamoto

Mr. Tetsuya Miyamoto

One of the most important skills you can have in the field of engineering is the ability to think progressively and outside the box. It’s always challenging to come up with novel ideas for your next project when there are so many other innovations out there already. So what does it take to be a progressive thinker? What is the right kind of mindset for success?

Tetsuya Miyamoto, a successful mathematician and the creator of  KenKen Puzzle, one of the top mental stimulation exercises that is featured daily in The New York Times, sat down with DevicePlus to share his thoughts on what makes a successful innovator. KenKen is a fun logic-mathematical puzzle originally designed for elementary children to practice addition, subtraction, multiplication, and division. The puzzle aims to foster creativity and improve reasoning and problem-solving skills. It gained immense success shortly after its introduction back in 2008, and it has spread globally ever since. Today KenKen is considered one of the world’s best brain exercises for people of all ages and it’s featured in more than 200 publications worldwide.

Mr. Tetsuya Miyamoto

Tetsuya Miyamoto, the creator of KenKen, shares his passion for innovation

The KenKen Puzzle

DevicePlus (DP): Please tell us about your invention. From where did you draw inspiration for KenKen?

KenKen was created to unlock children’s creative minds. I was initially inspired by Kakuro which is a numerical cross puzzle. The puzzles deal with additions only; each puzzle consists of a blank grid and the goal is to fill all the empty blocks using numbers from 1 to 9 so the sum of the each horizontal and vertical blocks equal the numbers written on the left and the top, respectively.

When I was asked to come up with materials for 3rd grade math classes, I wanted to create something that can help children engaged and have fun at the same time. I also wanted to include four basic mathematical operations, instead of just one.

This is how I invented KenKen. The first KenKen was a 5×5 puzzle. It is now available in a variety of sizes and challenge levels so anyone, including adults and seniors, can take on it.

DP: Engineering is all about discovering and solving problems. The same applies to mathematics. What does solving problem mean to you?

Some would say the most important thing in mathematics is calculation. You memorize the formulas and calculate to solve a problem. In my opinion, there is much more than just calculation. I think the process of challenging yourself with different questions and struggling to figure out solutions on your own is what makes solving any kind of problems more fun and meaningful. This is the reason why I never step in to help my students solve puzzles, because I do not want to risk taking away their invaluable learning experiences.

To me solving problem doesn’t mean just calculating to get to an answer, and math certainly is not just about solving problems. It’s the process of thinking and the learning that occurs during solving problems that make up a unique and rewarding experience. And this is very important because it also applies to life. Life is like climbing a mountain. Your goal is to reach the top of a mountain, and at times, it can get hard but you must keep going and challenging yourself. It can be a painful process, but trust me, this is the part where you’ll experience the most joy, when you get to the top.

What I call it, “Archimedes moment” is what problem solving is about. Archimedes, a Greek mathematician and engineer, would run around naked celebrating the discovery of buoyant force. I wouldn’t run around naked, but I do cherish that moment of solving the problem and bask in the moment of celebration when I solve a hard problem.

How to Think Progressively

DP: Is there any tricks to thinking outside the box?

There is no “trick” to thinking outside of the box. Thinking outside of the box means you take the same information that everyone else has and interpret it differently. My advice would be to never stop thinking!

Say you’re solving a problem, whether it be a math problem or any life-related problem. Be open-minded and never stop with just one solution. Instead, think about different sets of possibilities and ways to approach the problem.

Keep setting the bars higher and never stop thinking and challenging yourself. These are the essential attributes to thinking outside the box.

DP: In Engineering, failure is inevitable. Whenever we try to initiate new things, there is always a risk that a project will never go as planned. What is your advice on overcoming the fear of failure?

I say don’t fear it. Accept it and respect it. Failures are always learning experiences. Failures in engineering and in mathematics usually happen because of things we don’t fully understand. They often lead to a better result or product that we may not have been able to consider prior to that failure.

The thing is we can almost always never eliminate the risk of failure in engineering and in mathematics, as well as in life. The best we can do is to accept that there is a certain amount of risk and move forward by trying to minimize it.

DP: What do you suggest we do when we get stuck on a problem and we are on the verge of giving up?

Actually, it’s important to give up sometimes and let go. I’m not saying that you should never look back at the problem; you will probably encounter the same or similar problem later in your life. What is important is to embrace the situation and yourself that you couldn’t do it this time because you can only achieve so much at a time.  

My advice is to stop thinking about the problem and get some sleep! Interesting things happen while we’re asleep. Many many times I would get stuck creating puzzles. I would give up and and throw myself on my couch and sleep. Next thing I know, I wake up with solutions in my head. Don’t agonize over something you can’t solve at the moment. Get some sleep and you will have the answer by the time you wake up!

DP: How do you keep on challenging yourself?

I make a list of things I do not like to do and I pick one from the list that I absolutely do not want to do. Then, I set a date and get it done. This is my way of challenging myself and pushing past my limits. No challenge means no fun in my dictionary. If you want your goals and dreams realized, you need to work through them, and challenging yourself is a necessary part of progressing to the next level.

Challenges make you grow into a stronger person as you learn during your struggle.  My ultimate goal is not to be successful, but rather to keep on challenging myself, learn and grow. I’ve written more than 180 books but I never quit moving forward. I always try to have something that stretches me and makes me grow.

Mr. Tetsuya Miyamoto

“Always aim higher and keep on challenging yourself!”

DP: What is your next goal? What comes after KenKen?

I’m interested in making an online platform where people can play KenKen together, like a chess match. Each players can come up with their own puzzles and present them to each other and they can play live. It’s going to be very engaging.

KenKen is currently being used in one of the hospitals in Japan to help patients with depression. It’s able to mitigate depression by taking their minds off of depressing thoughts and boosting their self-confidence and self-esteem. I would like to further contribute to the study of the efficacy of KenKen as a treatment for depression.

DP: The technological developments in recent years have been profound. You can tell by looking at some of our projects on DevicePlus. What is your opinion on the advancement of technology?

Undoubtedly, technology has improved the quality of our lives in many aspects. I’m quite excited about new technologies designed to address our ever-changing needs. At the end of the day, however, there are things that only humans were and are capable of producing, for example, Mozart’s musical compositions or Shakespeare’s plays and sonnets. We should appreciate their creations and try to preserve those aspects of human life.

Advice for Engineers

DP: As a successful inventor, what is your advice for aspiring engineer entrepreneurs and startup founders who are actively seeking inspiration and looking to create the next big thing?

Well, I would say explore as much as you can, find the things you are most passionate about, and take time to really think about what you truly want in life. You should always ask yourself “What am I trying to achieve in life?”. I always communicate with myself in my head, asking bunch of questions about the things I see and I experience. You really need get to know yourself better before planning to accomplish anything.

A lot of things in life that are perceived as very wasteful, are actually important and not wasteful, yet a lot of things that are perceived important are not that important. What is important is to focus on the things that truly interests you and makes your heart beat. I suggest you make lists every time you experience something that sparks your interest.

Planning to achieving your set goals is also very important once you figure out what you want to do in your life. Persistence and repetition are the keys to success. Set challenges for yourself that help you maximize your full potential. I’ve said it once, but I’ll say it again. Keep challenging yourself and keep looking for opportunities to grow.

6x6 KenKen

6×6 KenKen displayed on Mr. Miyamoto’s Manhattan classroom blackboard

DevicePlus Exclusive KenKen

Want to challenge yourself? Try this!

From October, 2014. Mathematics for High Schools (math to high school) by Tokyo Shuppan (Tokyo publication).

Credit: From October, 2014. Mathematics for High Schools (math to high school) by Tokyo Shuppan (Tokyo publication).

This is a 9×9 Kenken without operation signs. The goal is to fill all the empty grids using numbers from 1 to 9. The numbers may appear only once in any row or column. Each horizontal and vertical cage (outlined box) equals the numbers written on the left and the top, respectively.
Check the answer HERE!

Interested in tackling more KenKen? Check out for additional puzzles and tutorials!