Many well-known problems of human reasoning disappear once you get a group of people together and let them talk about it.
It's a good way to see your ideas refuted or let stronger ideas win the day. Although there’s a risk of group think and conformity pressures, if you take a large and diverse enough group, you’re more likely to be exposed to the best reasoning, which will tend to win out over the majority opinion.
...doesn’t happen because you’ve studied some abstract logical form and come to valid deductions.
It happens because you know enough about how the world works to rule out certain possibilities as being unlikely or impossible.