Sadly, his fellow doctors dismissed the data and his theory. They kept doing the same thing and patients continued to die at the same rate.
Pasteur then gave up on his peers and took his message to med students who had no habits or preconceptions. These students readily adopted his suggestions and death rates rapidly dropped.
Observing the big difference in the willingness of his peers and the students to adopt the new approach, Pasteur supposedly quipped, "Science proceeds on the death of scientists."
It seems to me that voter ideology proceeds in the same way. There is a window between about 13 and 30 when - for probably 2 to 4 years - a person forms a worldview. After that, the software loaded up in the form of biases, processes, habits and preconceptions, the work of learning is largely done. The software in the form of memes (customs, mores, philosophy, norms, etc.) becomes hardware, something that is unlikely to ever again change.
Once your worldview is set, the world changes but you don't. You become increasingly dated in your worldview. You think the world should be based on kin and clan, not tribe or city. Or you think that women belong at home and not in the office. Or you think that wealth is zero sum and we need to seize and conquer rather than collaborate and create.
Memes are the set of norms and policies that define us as a people. Wearing Levis. Holding doors for women. K-12 education. Like genes, memes carry information that shape us. Genes shape biology. Memes shape society.
Memes proceed on the passing of generations.
If we still had people with us from 1600, we would still have kings and not presidents. If we still had people from 1850 instead of 1950, we'd still have child labor rather than public education. If we still had people from 1950 instead of 2005, we'd still have blacks in separate schools and unable to vote.
I've known and discussed politics with a lot of people. Not once have I witnessed a conversion experience of anyone over 30. (Probably even 25.) Software becomes hardware past the age of 30.
The Epic of Gilgamesh dates from about 2000 BC and is considered the earliest surviving work of literature. Gilgamesh learns at one point that while man is mortal, mankind is immortal. Each generation regenerates itself. And given the story includes a character - Enkidu, who emerges from the wild, raised by wild animals and ignorant of civilization - who has to be civilized, it suggests that the city of Babylon could turn you into a human and then make you immortal. One big difference after the Enlightenment is the notion that this process that transcends any one person also transcends any one way of living; progress replaced tradition. But progress is tough.
It's lovely to think that people learn or update their memes. And some do, bless their heart. But most of us do not and for that reason, social progress depends on people dying and the next generation coming along, willing to adopt new ways in part because all ways are new to them at the start.
Which brings us to millennials.
Of the 250 counties with the most old men, 241 voted for Trump. (Of the 250 counties with the most white people, 249 voted for Trump. Race is an even better predictor of voting than age.) Millennials, by contrast, voted overwhelming for the first woman president, as you can see in this map:
You almost wonder if the rapid pace of social change that defined earlier times has slowed because people live longer or if it has sped up because we have more education. In either case, it's obvious that the things millennials are comfortable with - minorities, same-sex marriage, public funding for universities, public healthcare - freak out the elderly who voted overwhelmingly to make America great again.