How we change what others think, feel, believe and do
What will make a person agree with group decisions, going along with what is suggested even if they significantly disagree with the decision? Here's some reasons why.
If it is me vs. the rest of the group and nobody else sees things my way, then this is far more likely to sway me than even if there is slight agreement or one person takes my side.
When a person feels utterly alone, they are far more likely to go along with others, even if they strongly disagree. But all it takes is one other person to show some understanding for the individual to consider pulling back.
Hence, if you are in a group where one person is disagreeing and you want nothing of their suggestions, it is important for all others to clearly state their opposing position, with no suggestion of compromise.
Three is a magic number for people to feel like they are in a group and so feel more powerful and able to speak with the authority of a group. This is also true for others outside the group. Seeing three people agreeing, they perceive a group and take it more seriously that one person or a couple of people.
Hence in a larger group, if a sub-group of three people arises, they can be far more influential than two. Four people increases this effect, but not as much as the step from two to three.
The reverse effect happens too. If there is a division within the group and I have three others on my side, I will feel confidence and be unlikely to be persuaded by the weight of those against me.
If I have to do something, then I am more likely to do what I should rather than what I want to do.
This effect is most powerful when the watcher knows what I should do is able to report back to the group on my performance. It also has a surprising effect even if I do not know the watcher and they have no idea what I am doing.
If I admire the group and like people within it, then this will have an additional persuasive effect in getting me to go along with their suggestions.
If there is disagreement within the group then this will make many people less certain about the right thing to do. Even one question sows the seeds of doubt and shows that there is not unanimity.
If I am not sure, then conflict amongst others will reduce my feeling that I should conform with others, even if they are disagreeing over different things or where I could take either side.
Much of the above is driven by social desirability, the basic need we all have (and which some have far more than others) to be liked by others.
Much of what we decide is based on what we think others will think and we often think they are sitting in judgement of us. in practice, others think far less about us than we assume.