|
|
Aspects of Scientific KnowledgeLet's start with facts. Of course, you know what a fact is. You should also know that something is not a fact just because someone says it is. Because the word "fact" is so loosely used in common speech, I will generally refer to observations and data, rather than to facts. Observations, of course, are made by seeing, touching, smelling, hearing and measuring things. Data is the information collected by these observations. For our purposes, consider "observation" to be the act of determining what actually exists and "data" to be the record of those observations. Also, keep in mind that it won't usually be necessary to keep that distinction in mind. A scientific law is a summary of a great many observations that can be generalized into a fairly broad statement. The intent of a scientific law is to describe nature, rather than explain it. For example, the Law of Constant Composition says that the composition of compounds does not vary from one pure sample to another, but it does not explain why. Inferences are distinct from observations because inferences are made by drawing conclusions from observations. One special type of inference is hypothesis. A person makes a hypothesis by speculating about why or how certain observations are related. A hypothesis is a tentative explanation. Scientifically, a hypothesis forms the basis for additional controlled observations which serve to test the hypothesis. In a sense it is a prediction that can be tested. After a hypothesis has held up under rigorous testing, it can evolve into a theory. A theory is a fairly well established and significant explanation for a broad range of phenomena. A model is somewhat like a hypothesis or a theory that focuses on how something functions. A model is quite often pictorial, mathematical or mechanical, but it does not have to be. In this lesson we talk about atoms. When scientists and philosophers first came up with the idea of atoms, they made a hypothesis. When scientists used the idea of atoms to explain why compounds followed the Law of Constant Composition, they created atomic theory. When scientists tried to picture what those atoms must look like (or be like), they developed atomic models.
E-mail instructor: Sue Eggling Clackamas Community College |
