1.2.2: Experiments
- Page ID
- 477232
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Careful experiments such as the one we discussed with the aluminum pellets are a hallmark of science. But science was not always done in this way. Two researchers in the 1600s proposed new ideas for exploring the natural world that turned the focus of science towards experimentation (also referred to as empiricism).
Francis Bacon (1561-1626) advocated for inductive reasoning in contrast to the deductive reasoning that was practiced by the scholastics at the time. Deductive reasoning was based on ideas, whereas inductive reasoning was based on observations. The challenge for Bacon was that if there was some flaw in the ideas that were used to perform the deduction, it would carry over into what was deduced (as we have already seen in this text). Bacon advocated for making several observations and from those observations a cause might be observed to emerge. This was the initial the basis for what we might now call a controlled experiment. In a controlled experiment, we change one of the variables and see what might happen while leaving other variables unexamined.
The year after Bacon died, Robert Boyle was born (1627-1691). There were still many scholastics at the universities who wanted to understand nature via deductive reasoning from ancient texts, but Boyle continued the focus on inductive reasoning and experimentation. Boyle expanded on these ideas to include the need to replicate an experiment, and even to record experiments that failed to achieve the expected result. Boyle's innovations were owing to both his curiosity and his considerable wealth, which allowed him to conduct such costly experiments over and over again. (Imagine how much more science could have been done at the time if everyone had access to the time and resources necessary to do such work?)
Some of what made this idea unique at the time was probably Boyle’s considerable wealth which allowed him to pay for these expensive experiments over and over again.
Boyle was credited for a gas law that we will discuss later in this text. The work of discovering it was largely done by others, but Boyle’s prestige and wealth resulted in him getting credit for its discovery. On one hand we can see how it might be unfair for Boyle to have this natural law named after him when the work was mostly done by others. On the other hand, it can be thought of as an example of how modern science works: a community of experimentalist arriving at a result through collaboration and sometimes competition.
Through the work of these and other scholars of the time, empiricism began to emerge as the most powerful form of scientific thought. The general process of experimentation involves observing nature, manipulating nature in some way, observing nature after this manipulation, comparing these results and then trying to explain them. A more formalized experimental process will be introduced in the next subsection.
Section Summary
- In a controlled experiment, one aspect of nature is changed and then observations are made.
- Replication of experiments was one of the initial aspects of the scientific method.
- In an experiment nature is observed, some change is made to it, additional observations are made, and then the results are compared.