Whenever a definition is offered for the purpose of influencing a person?s attitude or feelings towards the subject in question, we are dealing with a persuasive definition. As should be obvious from the name, the whole point is to ?persuade? rather than simply explain or clarify ? for that reason, persuasive definitions often aren?t considered entirely honest because they mask what they are really doing.

Persuasive definitions may be true or false, like lexical definitions, in that they may or may not be accurate in how they describe a concept. The actual goal of persuasive definitions isn?t really truth over falsehood, however, so describing one as false isn?t always useful. Frequently such definitions are evaluated by their users by how well they persuade others to accept certain conclusions and attitudes.

In the section on lexical definitions we looked at these two examples:

• 1. atheist: one who disbelieves in or denies the existence of God or gods.
  2. atheist: one who knows that God exists, but is in denial for some reason.

The first is a genuine lexical definition because it clarifies how the word ?atheist? is used; the second, however, attempts to influence people?s perception of atheists. The definition here is replete with emotionally charged language, especially for the normal target audience of evangelical Christians. Notice the sole focus on ?God? rather than the more general ?God or gods? and the insistence that atheists perversely deny something that they know and which others know that they know.

Persuasive definitions are probably most common in political debates ? people frequently define key terms in ways that make their opponents look as bad as possible. Thus opponents of abortion will define the practice as ?murder,? which makes supporters of abortion choice look like murderers. Libertarians will define ?taxation? as ?a form of theft,? thus making supporters of at least some sort of government taxation look like thieves, not to mention the government itself.

Although such definitions might be constructed in a manner to look like lexical definitions, they typically violate all of the rules needed for a definition to be lexical. They use, for example, emotionally charged language and are frequently negative rather than positive. Accepting persuasive definitions as if they were lexical is often the first step towards conceding an argument before it has even begun.

 

More: What are Definitions?