At some point in history — and not all that long ago — we did not know what in the world we were made of. We did not know anything about genes or cells or microbes or what made them all fit together.

We may have known the knee bone was connected to the thigh bone, but we didn’t know anything about the ligaments that shored up those connections, how all of that mattered to our muscles or why some old men had a lot more trouble walking than their grandchildren did.

For a long time, we didn’t know anything about bacteria or viruses either. We had no idea that they could threaten our lives, and we did not know that we could avoid the diseases they brought.

Scientists have taught us a lot about these things, often working for years to answer a single question to help us understand how things work and how they could work better.

“When I teach biochemistry, I often challenge my students to think about the people who made the facts in their textbooks possible,” said Catherine Leimkuhler Grimes, professor of chemistry and biochemistry at the University of Delaware.

“People. Real people made these facts possible, probably dedicating much of their research careers to discover these things. However, as we go through time, those facts can be added to and the plot can thicken and/or change.”

For a while, back in the Middle Ages, some people thought you could turn any kind of metal into gold. They dreamed up many kinds of methods and made wild claims, but they kept their work — which was called “alchemy” — secret, as magicians do.

Real chemists share their ideas and questions, the precise processes they use to test and/or measure things, what happens when they combine this with that, how things change if you shake things up or just add water. And they tell other chemists all about it. Sometimes those chemists will say “you forgot about this” or “this didn’t happen when we tried it” or “there is a fundamental problem with this part of your experiment that invalidates your conclusion.”

Those debates and exchanges can be quite uncomfortable. But they help to move science forward, as we’ve seen in this past year of pandemic.

Biologists, microbiologists and epidemiologists have helped us understand viruses and how they can spread quickly, even in people who have no symptoms of illness.

We understand now that washing our hands or wearing a mask can be life-saving practices — for us and the ones we love. We know that our bodies have important protective systems to defend us from viruses, bacteria and other dangers. We also know that viruses can adapt in ways that help them get around our immune systems and that vaccinations can be a powerful weapon to prevent severe illness or death.

These are life-or-death-level efforts that require integrity in the lab, in the notebooks, in reports and in public communications.

For example, health officials originally told us not to bother wearing masks when the pandemic first emerged. Then they changed their minds and said the opposite. Wearing a mask is now considered crucial to stopping the spread of COVID-19, as scientists realized — through experiments and studies — that the virus was spread through the air.

How do we know scientists aren’t just glorified hucksters, promoting a product or a political party or their own interests?

What happens if something we once thought was a fact turns out to be false, a mirage or a trick? The Cemetery of Dead Science has many graves.

Is there any such thing as a fact? And who gets to say what is a fact and what is a fraud? If someone says “I don’t believe the scientists,” what are they really saying? Is a gut feeling just as reliable, as some believe? Who and what can we trust these days?

The answers to these questions are embedded in the scientific method, the transparency and integrity it requires and the rigorous effort it represents.

“Science is built on answering questions with facts,” Grimes said. “Facts are learned through real experiments that generate data. Those data are real. At one time, it was believed that microorganisms were generated through spontaneous generation, that they magically appeared in the atmosphere. It took carefully designed experiments performed by Louis Pasteur to prove that this was not the case. But it was the question that ultimately drove the science.”

Asking good questions and pursuing fact-based answers are the hallmarks of excellence in research and foundational to future discovery.