Sounds counter-intuitive, right? Well, that might be because the word “participants” has been overstretched and overused to mean everyone who sits in a room where something is happening. So if you do a participatory activity (e.g. draw a Net-Map with a group) and there are 30 people in the room, they are all participants, right?
Well, not really. In my experience, if you try to squeeze 30 people around one table you end up with at least two rows of chairs and with a few very active participants in the front row and a large audience of people who just watch and listen to what is happening.
My numbers are based on experience and it can vary according to activity, culture (national and group culture) and facilitator skills, but as a general rule of tumb I would say: If 4-8 people sit around the table, an organic discussion can develop in which people choose their level of involvement according to what they have to say and with just a little guidance of the facilitator to encourage quiet ones and dampen the domineering ones. Let 9-12 people draw a Net-Map together and you will have to facilitate more assertively and be one of these people who can listen to two different things with your two ears, see two different things with your two eyes to make sure that everyone and every view has the chance to be heard. Above that number, you are likely to loose the ability to see and feel the whole group all the time, there will be more and more side conversations or just a quiet group of people who feel disempowered to speak because they don’t feel they have enough status, knowledge or their opinion doesn’t reflect the perceived mainstream of the group.
And the interesting thing is: The bigger the group, the smaller the number of active participants becomes. Not just in relative but in absolute terms. So, in a group of 7 you might have 7 active contributors. In a group of 20, most likely there will be 1-3 really active contributors and then some who say something every once in a while but most will not say a thing (unless they wisper it in their neighbors ear). One of the reasons is that saying something in a small group feels like engaging with your peers. Saying something in a large group feels like being on stage.
So, if you are looking for active participants and not just a quiet audience to a 2-man-Net-Map show, invite less people. And make sure they represent all the different views you want to learn about. Or invite more people but split them up into smaller groups.