Let's start with several definitions of charisma. Oxford gives two interesting ones. First, "compelling attractiveness or charm that can inspire devotion in others", and second, " a divinely conferred power or talent". I'm not sure that a public speaker at an academic conference needs to inspire devotion like they are some success guru or religious leader so this definition feels too extreme when saying that a good presenter is charismatic. The second one is a little better if you believe that some people are naturally good public speakers just as charisma might be thought of an an inherent trait in some people. (Duckworth and Dubner have an interesting conversation about Bill Clinton and why he is considered to be charismatic by so many people.)
On the podcast, Duckworth also said, "So I think charisma is a kind of— almost like a magnetic force that draws people’s attention in a very positive way. So when we think of somebody who is really charismatic, it’s like you can’t take your eyes off them. And they’re the star." I think a good speaker can be like this. Time flies while they are holding the microphone. Dubner added, "Mine would be something like charisma as the quality of— someone having the quality that makes me want to do what they do or believe what they believe." A good speaker can also be persuasive so this tracks as well.
After a bit more discussion, Duckworth said, "Here’s a narrower definition, because I don’t want it to just be people we like, or likability. I think that when most people think of charisma, they’re thinking about a public— public speaking, like TED or some other venue." And he's where things started to really get tied together.
Eye contact came up. Charismatic people make really strong eye contact and look at whoever they are talking to like they really matter. I feel that eye contact is something that can make or break a presentation. It's rare that an audience member will praise a presentation where the presenter looked mostly at the screen. A good presenter is constantly reading the audience's reactions to what he/she is saying but also making eye contact to build and maintain trust.
Charismatic people signal that the person they are speaking to matters. Dubner and Duckworth bring up Dale Carnegie and say that an event like a book signing, you would make eye contact and use the person's name. As a presenter, you might mention something you heard in an earlier talk or praise the last speaker in the room, something to show that this is a unique event and you aren't giving the same over-rehearsed talk. This audience matters to you.
Maybe the most interesting thing that was brought up was the idea of charismatic people signaling that they have high status. According to Duckworth, in order to be considered charismatic a person needs to give off the vibe of "I like you and I like me." For "I like you', see the previous paragraph. For "I like me", she explains, "How do you signal 'I like me?' Which is really a proxy for 'the world likes me.' That actually is a little more nuanced. But I think that smiling, or basically not being self-deprecating— maybe things like posture help. But I think the most effective way to do it is for somebody else to signal that you’re high-status, or that the world likes you." Doesn't that sound like a good presenter? Confident, not afraid to smile, no excuses or apologies, not putting yourself down, standing up straight... and these come after we submit a bio talking about what we have accomplished that makes us worthy of giving the talk and often we have someone introduce us to also signal that we were chosen to be here and "the world like us".
I found the podcast episode interesting and hope you will give it a listen or just read the transcript in the link. I also hope that the next time you have an opportunity to give a presentation you think not just about what you are going to say (the content) but also about how you are going to say it (the delivery). When you put these two things together, the results are usually positive. Just don't forget to finish on time, even if it means saying a little less than you wanted to. Going over your time signals that you didn't really like the audience that much after all.