How Do You Build a Culture of Healthy Debate?

If you as the manager continually demonstrate that you are comfortable being challenged, or yielding your idea to a superior one suggested by a colleague or subordinate, everyone who works for you will emulate that behavior. 

If you dismiss challenges or yell at people who challenge you, the culture of fear your behavior creates will dominate no matter who you hire or how great you proclaim it is to challenge assumptions.

Healthy debate is easy if no one is taking the results personally. 

Most heated debates involve people who have trouble separating their opinions from their identity. If I draw what turns out to be a bad idea on a whiteboard, in a healthy culture it’s reinforced that the idea is lame, but I’m not. I can still be smart and valuable. 

• Postmortem / Debrief: after every project, a long conversation should take place where people review what happened, what assumptions were made, what went well and what could have gone better. 
• Experimental attitude:  “Let’s try working this way for a week and see what happens.” The continual exposure to the cycle of “assumption, test, learn, repeat” diminishes fear around asking questions and raises everyone’s comfort with making, challenging and testing assumptions.
• Discuss books about thinking: Are Your Lights On? is a favorite for inspiring people to think more critically, and humorously, about everything.