I've had the honor of leading a few workshops in my local area, teaching the basic introduction to the cyanotype process. Teaching inspires me because it shows me that I have only begun to know my own mediums. In order to teach well, I have to carefully observe how other people problem-solve and offer useful, helpful, supportive information in response.
And so I say that the old saying, "those who can't, teach," is wrong.
It is wrong because teaching challenges you to step outside your own pattern of thinking. Teaching requires you to examine your practice, observe it, break it down, and see the parts that are effective and those that are not so effective. These are critical steps for teaching that also serve as self-reflection to deepen your own artistic practice.
And teaching can fill you with new ideas. When I teach, one of my largest goals is to inspire play in my students. When I watch people play with a medium, they often choose to surprising or unexpected things born out of their own unique approach and curiosity. I can soak that into my own thoughts, reflecting on their creative approach, and be inspired to try new things in my work.
During a workshop, I'm less concerned about precise techniques and more concerned with experiencing and understanding the medium. There is always room to improve technique on your own, and while technique does require experienced guidance, we more often forget to play when we seek to improve technique.
That's why teaching art is so worthwhile; it reminds you to experiment, to experience another way of looking at something. Those things are the foundation of critical thinking and creative endeavors.