Speak from your heart

Get the audience on your side

Professor Malcolm Longair
Cosmologist, Cambridge University, UK

Astronomy is a fortunate discipline in that everyone feels drawn to it. They want to understand our place in the Universe, how it came about, what will happen in the future, is there life on other planets and so on. So we automatically have an interested audience. There are a number of essential points in communicating successfully with the public. My rules would be as follows:

• Preparation, preparation, preparation. In communicating with the public, it is essential to prepare very well for what you have to say. When using PowerPoint, condense the content into a manageable presentation and choose the illustrations carefully. As one prepares the lecture, the places where careful explanation is necessary become obvious. From scratch, it takes me two to three days to prepare a new public lecture. Never underestimate how long the preparation takes. Make sure you can include videos, good graphics, etc. These break up the lecture. It is a challenge to keep peoples' attention for an hour.

• Always lecture about topics in which you have real expertise. You will get difficult questions and you need to be able to answer them authoritatively. If you try to bluff your way out of a difficult question, it will show instantly and the audience will wonder if they can trust everything else you have said. If the question is technically difficult and you do not know the answer, say so. The audience cannot expect you to be an expert on everything.

• Always treat the audience as equals and never talk down to them. You might be the expert, but they know that and you do not need to inflate your intellectual attainments.

• Never use jargon and avoid acronyms as much as possible.

• Practice speaking. It needs experience to get the speed and tone of the lecture right. For major and complex lectures, I often do a dress rehearsal to an empty lecture room speaking as if I were doing the real thing. This needs discipline, but it is worth it. When I gave the Hesse lecture at the Aldeburgh festival, which involved a lot of musical illustrations and accompanying musical scores, I practiced the lecture several times to make sure it would all work and be the right length.

• Be prepared for the "crank" questions. In cosmology, you will often be asked about God and what happened before the Big Bang, for example. Make sure you have secure views.

• You must really believe what you say and communicate your enthusiasm for the topic.

• From the very beginning, get the audience on your side. It is always worth communicating your enthusiasm for the lecture you are about to give. "I just love giving this lecture", "This in one of my favourite lectures".

• You must not expect the audience to understand everything you talk about. If you get through three big ideas, that is a real achievement. Remember that the audience will get the point of a key concept if it is repeated more than once - ideally it should be three times in slightly different ways.

• Always arrive at least half an hour before the lecture. There are often technical problems which need to be resolved. I normally plan on being there 3/4 of an hour before the lecture. Then run through the presentation to make sure everything works.