science (n.) – the intellectual and practical activity encompassing the systematic study of the structure and behavior of the physical and natural world through observation and experiment
To me, science is simply a cycle of observation and prediction. Humans have been using this tool since before written history. For example: if a certain place has food every summer, our ancestors could predict that the place would have food again next summer. In simple steps, the cycle includes:
- Observe some aspect of the world.
- Try to make sense of it (a framework).
- Make predictions using the framework.
- Go to step 1. (note: any step can be the first since it is a cycle)
The key that makes science work is the feedback loop. If new observations don’t match the predictions, new frameworks are necessary. These lead to new predictions. This self-correcting behavior means that science as a tool will get us closer to truth. I define “truth” as how the world actually is.
Sometimes people argue that science is the endeavor to perfectly describe the world in simple terms. One example is F = m*a. This is a simple equation that does very well as a framework, but really is just a best guess for many situations. In my view, any framework could be best; it need not be simple or perfectly correct. It should just match the observations better than any other framework.
For science to show us the truth also requires fundamental doubt. For any given framework, we must allow that the framework itself is false. This means that no assertion can remain unchallenged. There is no absolute authority because anyone can begin the cycle to determine the truth themselves.
However, the body of knowledge that describes the world has grown so large that it is impossible for one person to verify all the frameworks. To address this shortcoming, we use peer-review publishing and consensus-building. Peer-review publishing is where other experts in a field read and critique articles on new research. Since they are the most knowledgeable about a very narrow aspect of the world, their evaluation of new research is the most valuable. This means that non-experts cannot up-end an established framework unless they have new and relevant ideas.
As a scientific field develops, a few frameworks usually emerge. These frameworks and their predictions are pitted against one another until most scientists in the field agree on just one. This is called a consensus. For example, 97% of climate researchers agree that climate change is occurring and humans are causing it. Consensus can be dangerous as it amounts to an authority dictating the framework. So, why trust science? Since science necessitates doubt and researchers can make careers by overturning consensus, a framework that is closer to truth will always win in the long term.
The scientific method can also be applied to activities that aren’t hard science. For example, the states are laboratories of democracy. A social or economic framework/prediction can be observed at the state-level to determine if the framework is effective and desirable at the nation-level. As another example, poverty alleviation efforts have adopted the scientific method to observe which strategies are most effective (and under which circumstances).
Science can’t answer all questions. It might be able to answer the surprisingly difficult question “How did the universe begin?”, but it’s probably useless in answering “Why did the universe begin?”. So far though, science and the search for truth have achieved some pretty unbelievable results. It has enabled humans to walk on the moon and to split the atom, and even shown that we can evolve from single-celled life. It works pretty damn well, so listen to the experts.