Because I am a man with great wisdom about all things chemistry (and also a huge ego, in case you hadn’t noticed that already), people have asked me many questions about the scientific method over the years. I have included these questions here for your amazement and amusement.
Q: According to the scientific method, what does “replication” mean?
A: It means that for something to be considered meaningful, it has to be reproduced many times by many people.
One of the greatest examples of when this was important came with the cold fusion fiasco in the 1980’s. During this time, two scientists named Pons and Fleischmann held a press conference and announced that they had been able to make atoms fuse at room temperature. It would have been the greatest discovery in history.
Only one problem: They announced this before sufficiently reproducing their results. When other researchers did the same experiment, they found that nothing had happened at all. Because Pons and Fleischmann failed to reproduce their experiment correctly, they were permanently shamed and driven out of the mainstream scientific community.
For an unbelievably awesome account of Pons and Fleischmann’s stupidity, check out http://undsci.berkeley.edu/article/cold_fusion_01.
Q: How can the scientific method be applied in everyday life?
A: My neighbor is a jerk. Because of that, I like to screw with him. This caused me to perform the following experiment:
- Purpose: Drive my neighbor crazy.
- Hypothesis: If I let my dog poop in his yard, then my neighbor will freak out.
- Materials: Dog
- Procedure: During my nighttime walk with the dog, encourage him to poop on my neighbor’s lawn.
- Results: My neighbor just cleaned up the poop and politely suggested I not do that again.
- Conclusion: When I let my dog poop in my neighbor’s yard, then my neighbor didn’t freak out.
I also learned that my neighbor may be a lot nicer than me.
Behold, the glory of science!
Q: How did the scientific method change how people thought about the world?
A: The scientific method allowed people to start systematizing what they were learning.
Instead of just looking at a bunch of stuff that happened and making guesses, the scientific method taught them that they needed to plan out experiments that would allow them to determine what was really going on with a greater degree of precision.
Keep in mind, the scientific method isn’t really so much a set of steps to follow as it is a mindset. When scientists study a problem, their goal is to collect data that others can reproduce, and formulate experiments that will definitively either support or disprove their hypothesis. The steps of the scientific method you learn in class are just a formalization of this way of thinking.
Q: Is external review needed during the scientific method?
When you perform an experiment, it’s your job to come up with a reasonable way of testing some hypothesis. When you come up with this experiment, you need to collect data in a way that’s generally considered valid. Upon studying this data, you need to make sure that your data truly supports your conclusion.
That’s where external review is required. You may think you’re the most objective person in the world, but if you really want an experiment to work, you might accidentally interpret the results to fit your expectation. And if you do that, you can pretty much expect that you’ll get the wrong answer.
Q: To be termed scientific, what must a method contain?
A: It must have the following characteristics:
- It has to be something that can be tested with an experiment. No experiment = no proof.
- It must involve unambiguous measurements. If something “seems about right”, it’s not scientific.
- It must use reliable methods to collect data. “My psychic powers tell me…” doesn’t count.
- It must involve unbiased researchers. While nobody is 100% unbiased, good researchers do whatever they can to disprove their own experiments to make sure the phenomena really exist. This isn’t to say that you can’t learn things without doing the above, or that the scientific method is the only way to figure out what’s happening in the world. However, there are very real differences between what it means to “know something” in philosophy than there are in science.
Q: What are cognitive biases in the scientific method?
A: Cognitive biases are beliefs that cause us to misinterpret results in a way that supports what we already believe.
Let’s say that I’m performing an experiment to see if squirrels can be trained to attack children. I’ve spent my whole life working on my attack squirrel experiment, and I’m sure that this is the time that the squirrels will finally render the playground uninhabitable. It’s my moment to shine!
Well, I let out my squirrels and they wandered over to the playground. One of the kids jumped off of the slide and accidentally stepped on a squirrel’s tail. The squirrel bit the kid and then ran away.
My conclusion: Success! The squirrels attack children!
Of course, the true result is that nothing much happened. The squirrel wasn’t trying to eat the child – it was just trying to get away from the creature that was stepping on its tail. I wanted to believe it was true, so I interpreted the experiment in the way that would confirm my beliefs.
Good researchers are no less prone to this phenomenon than bad researchers. After all, everybody wants their experiment to work so they can publish the results and get a bucket o’ money. However, good researchers understand that they’re prone to this sort of error and attempt to compensate for it.
Q: What are iterations in the scientific method?
A: Iterations occur when you repeat and experiment in slightly different ways to pin down a phenomenon.
For example, if you want to borrow twenty bucks from your mom, you’ll probably ask her for twenty bucks. And it probably won’t work.
However, you still need $20, so you go to mom and ask if she could please please please give you $20. The result is that she still doesn’t give you the money, but she does look thoughtful for a moment, suggesting she considered it.
In your third experiment, you tell your mom that you need to give your friend $20 because it’s really important please please please because her grandmother is in a coma and needs lifesaving therapy that costs $20. With your respectful attitude and convincing story, you finally get your money.
And that’s an iterative experiment. By changing something a little bit every time, you’re better able to pin down the phenomenon you’re looking to understand.
Q: What are the basics of the scientific method?
A: The scientific method is basically the way that scientists study the world. The idea is that when you perform an experiment, you should do it in a systematic way that collects good data that can be reproduced.
Depending on who you talk to, there may be several steps to the scientific method regarding how to perform an experiment:
- Purpose: If you don’t have a reason for studying something, you probably won’t. This reason may be either broad or narrow.Hypothesis: Your guess about what will happen if you change some variable in the experiment. The independent variable is the one that you are manipulating, while the dependent variable is the one you are measuring. Usually phrased in the form “If I hit myself with a hammer (IV), my head will hurt (DV).”
- Design an experiment: Collect the materials (and funding) needed to perform the experiment, and come up with a reasonable procedure for doing it.
- Data collection: Your observations and measurements. Non-numerical observations are referred to as qualitative data, while measured quantities are called quantitative data. Both are present in all good experiments.
- Results: So, did it work or not? At this stage, you must take a good, hard look at the data and see if it supports your hypothesis.
- The big conclusion: If you think the experiment supported your hypothesis, then repeat, repeat, repeat. If it doesn’t, see if you can figure out something better from your data and start over.
Q: What kinds of questions can’t be answered with the scientific method?
A: Anything that you can’t study experimentally can’t be explored using the scientific method.
- “Is God real?” This is an important question that many people would love to have the answer to. However, until there’s a way to reproducibly measure the existence of God, it can’t be studied scientifically.
- “What’s the meaning of life?” This is way too subjective to be something that can be studied scientifically. First of all, it assumes that there *is* a meaning of life, and that it will be the same for everybody. Unless you have a way of testing this, it’s not scientific.
- “Are people fundamentally good?” Again, how do you test that in a way that answers it in a meaningful way? And how do you reproduce your experiment?
This is not to say that the problems above aren’t worth thinking about. Though scientists sometimes scientists believe that questions like this are stupid, this misses the point of our human quest for knowledge. Science isn’t some sort of magic answer finder, but simply one way of figuring out what’s going on around us. Just because it can’t do everything doesn’t mean that either science is flawed or that the things it can’t study are pointless.
Q: When was evolution proved by the scientific method?
A: Evolution has not been proved by the scientific method.
That’s not to say that evolution isn’t right, because it’s pretty clear from scientific data that it is. It’s just that nothing can be 100% proved using science. No matter what we do or what we believe, there’s always the possibility that we got it wrong. That’s the central idea to the scientific method.
For more information about evolution, see: http://en.wikipedia.org/wiki/Evolution
Q: Who invented the scientific method?
A: There’s no one person who came up with this idea on their own. Rather, developing the main ideas of scientific discovery took a very long time and was worked on by a large number of people.
One of the most interesting was Charles Sanders Peirce, who lived in the late 19th and early 20th century. It was he who was one of the last to really put the finishing touches on the idea of the scientific method, but I doubt that anybody would ever say that he did it on his own.