Diana Fisher
📊 "Stock-flow modeling is a superpower—making systems visible, transparent, and understandable. We must teach it to precollege students so they can tackle the complex challenges of tomorrow. Giving them this tool is not optional—it’s a responsibility." #SystemsThinking #Education #StockFlow #FutureReady
How did you first encounter systems thinking, and what made it "click" for you?
I first encountered System Dynamics at a conference for teachers who used computers in precollege education. That was 1990. I went to a workshop where Lola Piper, a high school teacher at Blair Magnet Program, was demonstrating how to build a stock-flow model of a population using the Stella System Dynamics modeling software. I liked the visual nature of the representation and thought it might help some of my algebra students understand mathematical concepts better. It took me a few months of practice with the software, after the conference, to feel confident bringing this model-building idea into my classroom. Students were very receptive. Then I realized I could have the students study more complicated real-world applications in algebra because the visual stock-flow representation approach was much easier to understand. At the same time I started having my computer programming students practice building stock-flow models. They took to the systems modeling approach even more quickly. It was as exciting for me as it was for my students. I have never quit learning systems thinking and System Dynamics modeling. It has stimulated my interest in learning more about other disciplines – especially biology, human physiology, environmental science and economics, learning them through the lens of stock-flow models.
What is a misconception about systems thinking that you wish more people understood?
Again, my focus was/is always on having students build stock-flow models. Some misconceptions – actually guidelines to help a person avoid misconceptions - about this model-building process for the students (and myself) were/are: • You cannot build a model of a system you do not understand. • Unit consistency is critical in model-building. Without consistent units a model is worthless. • It is important to build and test a model in stages. (Always have a working model.) • The greatest learning occurs in the process of building the model.
If you could give one piece of advice to someone new to systems thinking, what would it be?
Just like learning to use math (arithmetic through calculus) to understand the world from a different perspective from reading prose, learning to build even simple stock-flow models can help you learn (and strengthen your understanding) about the world from the perspective of feedback processes, interconnections, unintended consequences of policy decisions, interpretation of graphs and how they relate to the structure of a problem, nonlinear dependencies, and transfer of understanding about one systemic problem in one domain to understanding a systemic problem in another domain that has the same structure. It brings deeper analysis/insight to younger people because of the visual nature of the tools we use to represent our systemic problems. It is worth the start-up efforts required to learn to build simple stock-flow models due to the enormous pay-off of deeper learning. Younger children are better at learning this than adults because they are already in learning mode and are less afraid to fail. - It is worth your time and effort to learn this approach!!! Learning System Dynamics modeling has changed the way I think about (and understand) the world. This view matches how the real-world works more closely than how we currently teach many disciplines in K-12, especially how we teach mathematics.
Can you share a moment when systems thinking changed how you approached a real-world problem?
I am going to change this question a little. The most powerful moment in my precollege teaching career was when I realized the power that System Dynamics modeling provided for my students’ thinking. I taught a year-long System Dynamics modeling course for high school students for 20 years. The depth of thought behind the original models they built, demonstrated both by the stockflow models they created and by the technical papers they were required to write explaining how their models worked was so impressive. (University professors who read these papers said it was university quality analysis.) This experience showed me that student thinking had been hampered by the mathematical tools (equations) that we restrict for our students’ use to understand dynamics (especially in calculus – but also in algebra, where students can work with the concepts of calculus without the enormous equation overhead). This idea is best encapsulated by the quote “The limits of my language mean the limits of my world,” by Ludwig Wittgenstein. This realization changed the way I thought about teaching and thought about what students could learn if they had tools that supported their deeper ability to construct their understanding of the world. It changed me as a person and as a teacher.
What is one book, tool, or resource that significantly shaped your journey in systems?
I admire everything written by Donella Meadows. As a scientist and System Dynamicist she understood the world at a deep level, but she was able to translate that understanding in layman’s terms so the rest of us could move forward in our own systems journey. Her books Thinking in Systems, and articles collected in The Systems Citizen were/are a huge gift to others. I prefer using the isee systems software Stella for all my stock-flow modeling work. It is designed with education in mind. I have used this software since 1990 and the company has always maintained a special relationship with K-12 education, even though the software is used by economists, business leaders, government officials, medical personnel, etc. to study real-world systemic problems.
