Persuasion and coercion are complete opposites. The former is a peaceful means to an end, while the latter employs fear and threats to achieve results. Regardless, there are times when each tactic is useful or necessary. However, it is important to understand the difference before you make the mistake of improperly approaching an argument.
Simply put, persuasion is a form of discourse that attempts to convince others without hostility or threats. For example, parents try to persuade their kids to clean their room. Alternately, kids may use persuasion to increase their allowance or borrow the car. With persuasion, there is no "do this or else" statement involved. Persuasion is strategic and something that can be mastered. Lawyers, politicians and advertisers study persuasion extensively.
Effectiveness of Persuasion
Persuasion is a peaceful, non-threatening way to convince another person. Since its entire purpose is to open the heart and mind of another, any changes in the opponent's attitudes or actions are voluntary. In turn, this reduces the chance of ill will or hostility. Unfortunately, persuasion may not be the most useful for immediate results. Persuading someone can require a great deal of discourse. Additionally, persuasion is not an option under some circumstances, especially if the person is not willing to listen.
Coercion is radically different from persuasion. Rather than using words to convince another person, results are obtained through threats of violence or punishment. If you have the power or desire to punish an individual, this tactic is an option. For example, as an employer you can threaten non-compliant employees into doing a job for you.
Effectiveness of Coercion
With the right leverage, there is no doubt that coercion will get you what you want. In fact, it is sometimes necessary. For example, a dictator cannot be persuaded to simply give up his power. However, offering free elections will force the leader out of office, whether he likes it or not. Still, coercion should never be chosen if persuasion is an option. When coerced, people may be resentful and fight back by doing a poor job or simply getting defiant. Also, there can be legal consequences if the coercion involves violence.