Because that’s just good speaking. Chris Mooney has a very good post about the civic obligation scientists have to explain their work and its implications to the public. I recommend it highly. But one small part of the post rubbed me the wrong way (italics original; boldtype mine):
When it comes to scientific topics, citizens–and journalists, and policy-makers–want to know what the bottom line is, in plain language. They want to know why a topic matters, who it affects, what we can do about it. And can you blame them for feeling this way? There is a lot out there to pay attention to. We’re all suffering from information overload, all the time. It is very hard for anything to get through, much less anything technical or difficult.
This fact has huge implications for how scientists communicate, because it suggests an approach that runs strongly contrary to their instincts in many cases. Scientists are often prone to explain themselves through long, stepwise, technical arguments, eventually leading to some type of heavily hedged conclusion. So they’ll start out communicating like this: “I study X. X is a particular type of Y, found in Z. Previous researchers studying X had postulated that A and B most centrally influence its formation and development, but my work suggests that to the contrary, C plays the dominant role…”
And so forth. But what non-scientist is going to follow all the steps, trying to keep up with all the jargon and alien terms (here denoted by letters), without even knowing where it is all going to lead and why it matters?
That’s why scientists, in communicating, have to unlearn what they’ve learned in their training and put the conclusion first–followed by the details. For of course, once you understand why the details matter, you are more likely to grow interested in them and want to learn more. Yet this is very different from scientific instinct in many cases. It’s not how scientists are trained to talk to their peers.
Hunh? Because that’s not how I was trained to give a talk, nor is that a talk I would want to hear.
Even if you don’t put your all of your conclusions at the beginning of the talk, the main themes–and why you should spend an hour of your life listening to this–need to be upfront. Otherwise, it’s just a jumble of facts that don’t mean anything because they lack context. In fact, when I’ve been asked to help people review/practice their talks, that is the first thing that I (and usually everyone else in the room) beat out of the speaker.
For shorter talks, the twelve to twenty minute talks often given at conferences, I have a very simple formula, best described as ‘all of the Mad Biologist’s rhetorical gall can be divided into three parts’:
1) Part I: Tell them what you’re going to tell them.
2) Part II: Tell them what you’re telling them.
3) Part III: Tell them what you’ve just told them.
Hopefully, by the end, they might actually remember something (seriously, more than one or two key points in a 12 – 20 minute conference presentation is just a disaster waiting to happen).
I’m not saying that all scientists speak well (Sweet Baby Intelligent Designer that’s not true). But we’re not trained to speak poorly. Usually, poor speaking and keeping the punchline for the end is a reflection of no training at all.
Which is its own problem.
Nonetheless, Mooney still makes a lot of good points.