President Obama’s decision to replace the term “income inequality” reflects the importance of choosing words carefully to influence your audience.

The president decided to tweak his message to give it a more positive tone, so he began using such phrases as “upward mobility” and “ladders of opportunity.” Such word manipulation is a persuasive tactic that has been successful for almost a century. As far back as the 1930s, psychologist Alfred McClung Lee referred to this as using “glittering generalities,” words that resonate with an audience because of their positive connotations, even though they are ambiguous. “They mean different things to different people,” Lee said. “They can be used in different ways” and the audience is left to apply its own interpretation. The intent of the persuader is to induce people “to approve and accept without examining the evidence.”

Take “compassionate conservative,” for example. Most people will agree that compassion is a good thing, but what does it mean in that context? One side of the debate might say it is someone who supports slashing the social services budget by 30 percent, rather than by 50 percent, while others would argue that a 30 percent reduction hardly demonstrates compassion.

The burger industry knows that the term “fast food industry” evokes images of unhealthy food, so it began to refer to itself as the “quick-service food industry.” The industry chose a description that highlighted certain qualities and omitted others, thereby coloring the perception, in the minds of many. That’s how the tactic can make a message more persuasive.