How confident people are in convincing others to agree with them

Want to win more arguments? Use this simple four-word “hack,” says one influence expert: Make your explanation concise.

The more points you add to your argument, the less convincing it becomes, says Neeru Sivanathan, professor of organizational behavior at London Business School.

“Most people make a forecasting mistake, which is that in order to attract people, you need to give them a lot of data,” Sivanthan tells CNBC Make It. “Often, it’s not the content that fails, it’s the execution.”

This is called the dilution effect: your strongest claims are diluted by your weaker claims. People listening will walk away remembering the average persuasiveness score of each point you make, rather than your single most persuasive argument, Sivanthan explains.

If you’re trying to convince your friend that New York is the best city in the world, for example, you might cite pizza, Broadway shows, public transportation, and Times Square. Depending on your audience, some of these points will be more persuasive than others, and it’s best to only use the points that are most likely to win you over.

“Less is more,” Sivanthan says. “If you only have one main argument, be confident and bring it to the table, rather than feeling the need to include several others.”

The opposite of this strategy also works, according to Sivanthan’s research. His 2017 study found that after watching commercials for a drug, consumers were more likely to view a drug favorably when companies listed moderate side effects immediately after severe ones.

Using the softening effect to make your arguments more persuasive can be “a very easy solution,” says Sivanthan. This can help you get a job, shorten presentations, and make dinner table discussions friendlier.

It requires self-control. Once you have made your main argument, you should be comfortable leaving it in silence until the other person is ready to respond. Otherwise, you’ll find yourself unwittingly jumping back in with additional weaknesses.

“People have a problem with silence,” says Sivanthan. “When there is an empty space, you feel the need to fill it with words.”

It’s a common mistake, even for people who argue for a living. “You’ll see it in political campaigns and debates….. (they) should have stopped after (point) No. 2, but ‘I’ll go to three or four,'” he adds. “

Research shows that silence is a powerful negotiation tool, and often leads to better outcomes for both parties. Mark Cuban, the billionaire investor on ABC’s Shark Tank, uses this strategy often: After a contestant pitches his pitch, he initially tends to stay quiet while the other panelists argue and discuss details.

If he decides to make an investment offer, it will be after he has had time to analyze the strengths and weaknesses of any potential deal, he said during a conversation at Fireside in June.

“The more you pay attention and awareness, the better chance you have of getting what you want,” he said. “Silence is…money in the bank.”

This is smart, says Sivanthan.

“A lot of the impact is taking the time to think about (the arguments),” he says. “Those who are good at meetings and (communicating) with people…have thought about it a lot. This is not a coincidence.”

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