There are certain pervasive stereotypes that society holds about scientists. These stereotypes are often reinforced in the media: popular TV shows, big-budget movies, off-hand comments in the news, and so on. In this view, scientists are usually old, white dudes with unkempt looks who shun the world in favor of their "experiments" (quotes here because they're usually not well controlled or maintained properly, but I digress) in their disorganized laboratory. Their passion for their work dominates their lives to the point that they are essentially no longer recognizably human.
Occasionally you'll see a younger scientist portrayed. They're at least not old, but still manage to have some crippling personality trait that prevents them from having normal personal interactions. They're ridiculously smart to the point of improbability, and also largely suffer from single-minded devotion to a single task.
Overall the message is this: a scientist is not the kind of person you want to be, it's something that happens to some people.
But how many times do scientists not actually mind the stereotype, and even actively work to encourage it? I've met more than one scientist who deliberately puts on an air of aloofness, who has judged society to never be able to understand their work, or who thumbs their nose at social conventions because they're too important.
Sometimes we take on the way that society portrays us and wear it as a badge of honor - a way to distinguish us from them. Which of course isn't exactly healthy.
If there's a nugget of positivity in here, it's that scientists are at least shown to be passionately curious, which I argue is one of our defining - and admirable! - traits. That curiosity drives the late-night programming sessions, the wrestling with tortuous mathematics, and the rigorous attention to laboratory detail. But scientists themselves are a broad cross-section of people and personalities - and almost never like how the media portrays.
To break down stereotypes, we can't just sit around complaining to each other about how we're portrayed in the media; we actually have to go out there and show people what real scientists look and act like.
You know, provide some evidence.