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Epistemology -- How do we know?

A critical component in understanding of scientific knowledge and develop is in understanding how we know what we know; that is, how data, principles, plus reasoning lead us to conclusions.  Even at the college level, many students view their science courses as providing information and procedures given by experts.  But in order to become experts themselves, students have to develop an understanding of how the expert community has come to the knowledge it has. 

One component of building a competency in understanding scientific reasoning is developing epistemological resources that allow them to understand the extent to which a claim is adequately supported.  This includes a variety of skills.

1. Students should be able to determine whether a given set of information enhances the likelihood of a conclusion, reduces the likelihood of a conclusion, or is irrelevant to a conclusion.
2. Students should be able to evaluate whether stated assumptions for drawing a conclusion are reasonable or whether they need further support.
3. Students should be able to estimate when ignored factors are significant, irrelevant, or need to be considered more carefully.

Sample test items

1. A nice cup of tea

2. A positively charged object is placed close to a conducting object attached to an insulating glass pedestal (a). After the opposite side of the conductor is grounded for a short time interval (b), the conductor becomes negatively charged (c). Based on this information, we can conclude that within the conductor   Both positive and negative charges move freely Only negative charges move freely. Only positive charges move freely We can’t really conclude anything.   (From E. Mazur, Peer Instruction)

3. A Thomson’s gazelle can accelerate from rest to a speed of 90 km/h in 20 seconds and it can then maintain that speed for some time. If we want to calculate the distance the gazelle travels while it gets up to speed, identify all of the following statements that are true about this calculation.

1. The information given is sufficient to do the calculation since we can get the average velocity given the initial velocity (0 km/h) and the final velocity (90 km/h).
2. Although the information given is sufficient to do the calculation, we can’t do it since the units given are inconsistent.
3. Although we have the initial and final velocities, we can’t calculate the distance unless we assume that the acceleration is constant.
4. Although we have the initial and final velocities, we can’t calculate the distance even if we assume that the acceleration is constant. We need additional information.

4. Bizarre behavior with light