Todd Simkin on Lev Vygotsky’s ideas of teaching by finding the apprentice’s zone of proximal development (ZPD)
Simkin leads Susquehanna’s trader training programs. In the interview he explained how he and the firm approach teaching:
Simkin: When I was originally studying education [at University of Virginia as an undergrad], I was thinking that I might be teaching sixth grade deaf kids how to do math. Instead, [at Susquehanna] I’ve got MIT graduates who certainly understand math, but don’t know trading. And I’m teaching them how to make these asset allocation decisions with imperfect information. But the approach is still the same.
The approach is still this one of modeling the process, finding out where somebody is, and finding out what they can grow to and providing the appropriate support so that they can grow to be a better decision maker.
The philosophy that always comes to mind when I think about it is [the one put forward by] Lev Vygotsky.
So Lev Vygotsky was a Russian psychologist, born at the end of the 1890s, who grew in prominence in Russia pretty quickly through mid 1930s. He died young, when he was 37 years old, in 1934. The ideas that Vigotsky had around education were contrasted with another prominent psychologist of the day, Jean Piaget. Piaget had this perspective about stages of receptivity to different types of education, that you cannot teach somebody anything until they reach the appropriate developmental stage to be able to learn it. And then, they can learn whatever’s sort of presented to them before moving on to the next stage. And Piaget had, you know, a pretty rigid framework for the stages that you move through, how you move through them. And that education effectively ended at adolescence.
And Vygotsky said, “No, that’s kind of bunk. That’s not how any of this works. All of education is socio cultural, all of education comes from interaction with others. And those others in order for them to be educators have to be more knowledgeable than you are.” And that when you have interaction with more knowledgeable others, what those people are able to do is recognize your zone of proximal development (ZPD). You have a zone of things that you know, and then you’ve got a zone that is just too far out of your reach. No matter what, if I were to sit down my six year old nephew, and try to explain linear algebra to him, he’s not going to get it yet, he just doesn’t have the fundamental tools to do that. But somewhere outside of your zone of mastery is this zone of proximal development, the zone that that you can move into with appropriate support and that support, in the Vigotsky literature, is referred to as scaffolding. And you want it to be the minimal amount of support necessary to appropriately move somebody to be able to handle the next level of mastery.
Over time, you can dismantle that support, dismantle that scaffolding and that zone becomes part of their zone of mastery, and you’ve just pushed out where their zone of proximal development is. So that over time you can move them into an area where they’re learning more and more, and they’ve got greater mastery and competence in whatever area is that that you’ve been teaching them. Eventually, they become more knowledgeable than other people around them. And they can provide the scaffolding as the more knowledgeable other for their peers as well.
This use of ZPD defines “teachability” of the child in a specific activity or in problem solving. If an activity or problem can be accomplished by the child with the help of more capable others, this activity or skill is considered possible to teach the child. If, however, the activity or skill cannot be accomplished by the child with the help of more capable others, it is considered not useful to teach to the child.
Unlike Piaget, who believed that instruction should follow development, Vygotskij argued that guidance can, should, and does lead development. They would differently define what is currently called “developmentally appropriate curriculum.” Piaget insisted that learning is essentially an individual endeavor and that adults can only facilitate by providing an enriched stimulating learning environment and opportunities for children to share and discuss their egocentric thinking with each other to promote disequilibrium in the child’s thinking. Adults should not interfere in the child’s individual thinking because it can only lead to imposition of the adult’s ideas onto the child—what Piaget called “sociocentrism.” In contrast, Vygotskij encouraged adults to provide guidance and help and to engage students in activities that are beyond their individual levels of competence (“performance before competence” (sidenote: Whole Language Plus: Essays on Literacy in the United States and New Zealand by Courtney B. Cazden et al., 1992.) ).
Some researchers have tried to develop a “ZPD test” — a standardized assessment of a student’s teachability. However, it is doubtful that a reliable ZPD test could be developed because, as Newman et al. (sidenote: The Construction Zone: Working for Cognitive Change in School by Denis Newman, Peg Griffin, and Michael Cole, 1989.) demonstrate, the notion of ZPD is relational. A student’s teachability depends not only on the student but also on the teacher (and broader communities in which the child participates). Thus, no test of the child alone would accurately determine the child’s teachability — the teacher always counts. (#)
Back to Simkin.
Later in the interview he gives another example — this time in recruiting — of how the idea of ZPD permeates what he does:
Simkin: [Now, talking about our] hiring process. The best outcome for me for an interview is if the candidate walks away and wishes they could have part of the interview back.
That means that I did not spend the entirety of the interview in their zone of mastery, where they just got to show off and primp and preen in front of me. And then I left to decide whether or not they would have the skills to do more.
And [that also means] I did not spend the entire time in their zone of frustration, where they couldn’t do anything. Like, “Okay, I didn’t expect you to [be able to do it] any way, but, you know, if you could, that would have been great to see.” And I still [have to] make a hiring decision.
But, instead, on multiple dimensions, I’ve been able to find the place where, with a little bit of support, they could do a little bit more.
A big part of the reason that I like that is this thing, this openness to feedback. Because when I’m giving them feedback (because I’ve successfully mapped out their zone of proximal development), and now I’m providing a little bit of scaffolding to see what they can do with support.
You will find that some people embrace it and say, “Oh, I think I see where you’re going. Let me see if I can take it from here.” That’s a great answer. You will find some people who are just waiting for you to give them more of the answer. Who will just say “Okay, what else?” [They] wait for you to map out the entire selection process and then they’ll just fill in the numbers. I think you’ll find some people who are totally resistant to it, who will shut you up, who will put their hand up and say, “No, no, no. Let me work on it my way.” And they’re always not working. And I know why it’s not working. And I can help direct them away from it. But they don’t take the feedback.
I don’t want the person who doesn’t take the feedback. And I don’t want the person who’s waiting for more feedback. I want the person who is hungry and eager to use the tools that are presented and available to them to then do the work themselves. That’s what’s going to be successful when they’re trading. And they get to have a small opportunity of doing that in the interview process.
It jumps to me that a lot of experience is required to be able to dynamically assess where others are in their learning journey (while, at the same time, continuously adjust testing questions). But I guess that’s what makes great masters great.
It’s also interesting to note that Simkin is actively selecting for coachability.
By using the Socratic method (sidenote: Wikipedia: “The Socratic method (also known as method of Elenchus, elenctic method, or Socratic debate) is a form of cooperative argumentative dialogue between individuals, based on asking and answering questions to stimulate critical thinking and to draw out ideas and underlying presuppositions.”) , a teacher can zero in on where the student’s boundaries are.
By eschewing explanations and relying on repeated questioning, a teacher may quickly learn the map of a student’s existing understanding, and better guide them to the insight that is the goal of their conversation.
But there are also big limitations to the Socratic method. It’s true that the method works for well-structured and well-scoped ideas — ideas like learning a programming construct, for instance, or the key points of a philosophical worldview.
To borrow several terms from epistemology, the Socratic method works wonderfully for “know-what” (facts) and “know-why” (science). But it begins to fail the further we move away from such explicit forms of knowledge, towards embodied or tacit knowledge. This is the technê I’ve mentioned so often on Commonplace — the idea that certain types of knowledge cannot be easily expressed through words, and may only be learnt through practice or apprenticeship. These forms of knowledge are things like applying a martial art, kneading dough, riding a bicycle, or playing a musical instrument.