Science Test Topic 1 – Free
The Nature of Science
Science is both a body of knowledge and a set of practices. Science can tell us how fast objects accelerate toward the earth (an example from its body of knowledge), and how to determine this value (the set of practices). Scientific practices include such things as making inferences, designing controlled investigations, analyzing data, evaluating arguments, and communicating results. It is through scientific practices that scientists establish a body of knowledge. Science can serve many purposes, such as description, classification, explanation, and prediction.
Science is different from other disciplines, like psychology or philosophy, because science is based on empirical evidence. The word empirical means based on or verified by observation or experience. A good example of the idea of empirical evidence is the law of gravity. Gravity is something that has been verified by many experiences and observations over time, such as the apple falling on Newton’s head and Galileo dropping objects from the Leaning Tower of Pisa in Italy.
Though many things can be observed or experienced, not all questions can be answered by science. Questions that require opinion, belief, or judgment cannot be answered by science. For example, science cannot answer the question “what is the best color,” because the answer to this question is an opinion or judgment.
Observation and Inference
In science, a distinction is made between what we can observe, and our explanation of those observations. An observation is something we can notice using our five senses: sight, touch, smelling, hearing, and taste. An inference is a possible explanation for what we observe. The difference between an observation and an inference can be understood by observing the diagram below:
Taken from: http://artofteachingscience.org/text2nd/footprint_image.gif
Observations that a scientist could make about the image include:
- There are two different sets of what look like footprints
- The sets of footprints appear to travel down the page
- The larger footprints are spaced farther apart on the top of the picture
- There is a cluster of footprints in the center of the page
- One set of footprints appears to leave the cluster and continue travelling down the page.
From these observations, a scientist could make the following inference: a larger animal ran and attacked a smaller animal for food. What characterizes an inference is that it goes beyond what can be observed, and attempts to explain what is observed. It is important to note that inferences can be correct or incorrect. Scientists must not only base inferences from careful observations, but they must also acknowledge if there are other inferences that could be made. For example, using the picture above, another scientist might infer (the verb for inference) that two animals ran to a source of food, and one animal stayed behind to finish eating, while the other continued.
The process of science often involves making inferences, yet scientists must be sure to base those inferences on careful observations. Also, scientists must acknowledge other possible, reasonable inferences.