Unlocking Team Superpowers: Cognitive Diversity and Psychological Safety

In today’s increasingly complex technology, product, and commercial landscape, the importance of fostering diverse and psychologically safe teams cannot be overstated. This article aims to highlight the transformative power of cognitive diversity and psychological safety in creating collaborative, innovative, and successful teams.

I was wrong about what makes a great team

When I first started leading teams, I had a very clear picture of what made a team great. I used to think it was simple; that a great team consisted of smart people who got along well and got stuff done.

Fast forward ten years or so, and I realized my understanding of what makes a good team was wrong. The best teams I had worked with disagreed all the time! They did great work together because they cared, and they were smart in different ways, with different perspectives, but united behind a common goal and shared understanding. As I reflected on this, I noticed that teams I had thought of as “great” earlier in my career often lacked breadth of experience and perspectives. They rarely had difficult conversations, which I initially thought was brilliant. Eventually I realized that those teams were a homophily – a group that implicitly loved sameness. While we really enjoyed our time together, wow, did we write some mediocre software! Perhaps because we thought alike, had similar backgrounds, and prioritized not upsetting each other.

Perhaps I was not alone in my misconception. In almost all the interviews I take part in, when I ask the question “What’s the best team you’ve ever worked in?”, candidates often recount tales of working with great people who got along really well, working fast, with very little disagreement. Rarely do candidates mention the importance of diverse perspectives in their team, of challenging views, or of cognitive diversity.

The Cognitive Diversity Superpower

Cognitive diversity refers to the inclusion of different perspectives, experiences, and thinking styles within a team. It’s not just about demographic diversity but about harnessing varied viewpoints to solve complex problems. Teams with cognitive diversity are better equipped to innovate and make informed decisions. First, let’s look at the problems that can happen in team without a variety of viewpoints.

Homophily and Perspective Blindness

Homophily, literally “love of sameness,” operates like an invisible gravitational force, pulling teams and organizations towards having similar views, ideas, and perspectives. People tend to hire those who look and think the same, and many of us unconsciously enjoy being surrounded by people who share our perspectives. This comfort and validation can lead to perspective blindness, where our habitual ways of thinking filter our perception.

The late David Foster Wallace used to tell the story of two young fish swimming along, meeting an older fish who asks, “Morning, kids, how’s the water?”. The young fish swim on, before eventually turning to each other and asking, “what the hell is ‘water’?!”. This story illustrates perspective blindness – that our way of thinking and perceiving the world is so habitual that we scarcely notice how it filters our perception.

Collective Blindness and Groupthink

If you’re surrounded by similar people, you’re likely to share each other’s blind spots and reinforce them, leading to collective blindness and groupthink. That’s where a collection of people, perhaps in a homophily, grow together to converge and mirror their perspectives, ideas and attitudes – limits thinking and having a lack of effective challenge.

Many years ago, I joined a new employer and was put onto a great team on my first day. The team was full of the most talented people I had ever worked with; unbelievably smart, engaged, and friendly. They had worked together for a long time too, and had been really successful, bringing a new product to market. But what I saw in the following weeks was surprising. The developers working waaay ahead of test, they were cargo-culting Scrum, the architecture of the software was creaking, and the continuous integration process was glacial. Despite their individual brilliance, they had significant issues in how they worked. They had a collectively blindness, unable to see problems that were apparent to a less acclimatized new joiner (me).

Embracing Cognitive Diversity

Matthew Syed, in his brilliant book “Rebel Ideas: The Power of Diverse Thinking,” promotes the idea that by embracing cognitive diversity, fostering constructive debate, and harnessing collective intelligence, individuals and organizations can improve problem-solving, make better decisions, and drive innovation. He convincingly argues Cognitive diversity is crucial for dealing with complex situations where it’s impossible to identify one “correct” solution ahead of time or predict cause-and-effect relationships.

He recounts the work of Professor Jack Soll, a psychologist at Duke University, who analyzed 28,000 financial forecasts by professional economists. Economic forecasting being a hugely complex, perhaps even chaotic, domain. He found that the collective, averaged judgment of the top six economists in his study was 15% more accurate than the top-ranked economist. Put simply, top 6 economists together created a more accurate forecast that the number 1 individual performer. Why? Well, each individual economist has a different frame of reference and a different “model” to apply, with differing strengths and weaknesses. By amalgamating the forecasts, weaknesses were overcome with the strengths of others, and varied perspectives created a more complete picture, closer to the truth.

It’s not always a comfortable process though. Professor Katherine Phillips of Columbia Business School ran an experiment with her peers to test the value of diversity in teams. She found that groups with an “outsider”, someone with a different background or social group that their teammates, performed better in solving a murder mystery. Groups with an outsider got the right culprit for the murder 75% of the time, compared to 54% for homogenous groups and 44% for individuals working alone. What was especially interesting was that the diverse teams rated the exercise as more challenging, had more disagreement, and felt less certain of their conclusions, while homogenous teams found the exercise super agreeable, but were generally more wrong.

The Psychological Safety Superpower

So, if you ensure your teams have cognitive diversity you are done, right? Teams are guaranteed to be great? Unsurprisingly – no. You can have all the diversity of thought and perspective in the world, but if people don’t feel able to share their insights, or groups are not ready to value everyone’s input, it won’t do you any good. Psychological safety is the belief that one can speak up without fear of punishment or humiliation. It’s crucial for fostering an environment where team members feel safe to share ideas, concerns, and mistakes. High psychological safety leads to better collaboration and continuous improvement.

Amy C. Edmondson, a Harvard Business School professor, coined the term “psychological safety” while studying medical teams in hospitals. She found that high-performing teams admitted and discussed their mistakes, feeling safe to talk about them and improving their performance. In 2015, Google set out to answer what makes teams successful through “Project Aristotle.” They found that the clearest predictive behavior was high psychological safety. Teams that talked about problems and felt safe to raise issues and discuss, were more successful.

Building Psychological Safety

Amy Edmondson’s work outlines various strategies and practical steps to cultivate psychological safety:

1. Communicate Courageously: Model behaviors that encourage open communication, demonstrate humility, admit mistakes, be vulnerable, and reflect on what you’ve learned and what you don’t know.
2. Master the Art of Listening: Listen to understand, develop the discipline of not preparing a response, be present, clarify your understanding, and commit to curiosity.
3. Manage Your Reactions: Respond, don’t just react. Hit the pause button when receiving a rebel idea or difficult feedback, model non-defensive reactions, and appreciate being challenged.
4. Embrace Risk and Failure: Make it safe for someone to speak up and surface a mistake, normalize failure, and model learner behavior.
5. Design Inclusive Rituals: Have structure, rules, and roles in collaborative or creative meetings to ensure everyone can contribute equally.

Psychological Safety in Redgate’s Engineering Teams

At Redgate, we ask our engineering teams to fill out monthly surveys to gauge their psychological safety. In our latest survey at the time of writing (March 2025), 96% of our team members agreed that they feel able to bring up concerns and tough issues in their teams. This is a good position for us to be in, but I can’t help but worry about the 1% who told us they disagree with the statement! Even so, to maintain this level of safety, especially as we increase the demographic diversity of our engineering department, will require our leaders to remember the value of cognitive diversity and psychological safety, and actively nurture a sense of belonging and inclusion in every one of our teams.

In Conclusion

To unlock the full potential of our software engineering teams, we need to embrace cognitive diversity and nurture psychological safety. By doing so, we can create an environment where diverse ideas and feedback are valued, which will increase our likelihood of high performance and, ultimately, success.

Recommended further reading:

• Rebel Ideas: The Power of Thinking Differently by Matthew Syed
• The Fearless Organization by Amy C. Edmondson
• The Psychological Safety Playbook by Karolin Helbig & Minette Norman