"With rational messages, you need to decide if you want to use a one-sided argument or a two-sided argument. A one-sided argument presents only the pro side of the argument, while a two-sided argument presents both sides. Which one you use will depend on which one meets your needs and the type of audience. Generally, one-sided arguments are better with audiences already favorable to your message. Two-sided arguments are best with audiences who are opposed to your argument, are better educated or have already been exposed to counter arguments."