Philosophy: Philosophy of Science: What Makes Knowledge Reliable
Evaluating evidence, methods, and trust in scientific knowledge
Philosophy: Philosophy of Science: What Makes Knowledge Reliable
Evaluating evidence, methods, and trust in scientific knowledge
Philosophy - Grade 9-12
- 1
In your own words, explain what it means for knowledge to be reliable. Then give one example of reliable knowledge and one example of unreliable knowledge.
Focus on whether a claim can be checked and whether the reasons for believing it are strong.
Reliable knowledge is knowledge that has strong support and can be trusted because it is based on good evidence, careful reasoning, or repeated testing. An example of reliable knowledge is that water boils at about 100 degrees Celsius at sea level because this can be tested repeatedly. An example of unreliable knowledge is a rumor about a medicine working without any evidence or testing. - 2
A student says, "I know this energy drink improves memory because I drank it before a test and got a high score." Explain why this is not enough evidence to make a reliable scientific claim.
This is not enough evidence because one person's experience does not rule out other explanations. The student may have studied more, slept well, already known the material, or guessed correctly. A reliable scientific claim would need controlled testing with many people and comparison to a group that did not drink the energy drink. - 3
Define the difference between observation and inference. Give one scientific example of each.
Observation is what is noticed or measured. Inference is what you conclude from it.
An observation is something directly noticed or measured, such as seeing that a plant grew 3 centimeters in a week. An inference is a conclusion based on observations, such as concluding that the plant grew faster because it received more sunlight. - 4
A researcher tests whether a fertilizer helps plants grow. One group of plants gets fertilizer, and another group does not. Both groups receive the same water, light, and soil. Explain why controlling variables matters for reliable knowledge.
Think about how a fair test removes competing explanations.
Controlling variables matters because it helps researchers identify what actually caused the result. If water, light, and soil are the same for both groups, then differences in plant growth are more likely to be caused by the fertilizer. This makes the conclusion more reliable. - 5
Explain why replication is important in science. Use an example in your answer.
Replication is important because a result is more trustworthy when it can be repeated by the same researchers or by other researchers. For example, if many labs find that a vaccine reduces the risk of a disease, the conclusion is more reliable than if only one lab found it once. - 6
A study is funded by a company that sells the product being tested. Does this automatically mean the study is false? Explain what a careful thinker should consider.
Bias is a reason to examine evidence more carefully, not a reason to reject it without review.
This does not automatically mean the study is false, but it does create a possible conflict of interest. A careful thinker should look at the study's methods, data, transparency, peer review, replication by independent researchers, and whether the authors reported funding clearly. - 7
Describe the role of peer review in making scientific knowledge more reliable. Also explain one limitation of peer review.
Peer review helps make scientific knowledge more reliable because experts examine a study before publication to check its methods, reasoning, and conclusions. One limitation is that peer review can miss errors or bias, so it does not guarantee that a study is correct. - 8
Look at this claim: "Scientists once changed their minds about the cause of a disease, so science cannot be trusted." Explain why this argument misunderstands science.
Reliable knowledge does not have to mean unchanging knowledge.
This argument misunderstands science because changing conclusions in response to better evidence is a strength, not a weakness. Scientific knowledge is reliable because it is open to correction when new observations, experiments, or methods show that an older idea was incomplete or wrong. - 9
A graph shows that ice cream sales and drowning incidents both increase during summer months. Explain why correlation alone does not prove causation.
Correlation alone does not prove causation because two things can increase together without one causing the other. In this case, warmer weather may cause both more ice cream sales and more swimming, which can lead to more drowning incidents. A reliable causal claim needs more evidence than a pattern in data. - 10
Compare skepticism and cynicism. Which attitude is more useful for evaluating scientific claims, and why?
One attitude asks for evidence, while the other tends to reject claims automatically.
Skepticism is the practice of asking for good reasons and evidence before accepting a claim. Cynicism is the habit of assuming claims are false or dishonest without fair evaluation. Skepticism is more useful because it keeps an open mind while still demanding evidence. - 11
A website claims that a new treatment cures a disease, but it provides no data, no description of methods, and only personal testimonials. Identify at least three reasons this claim is not yet reliable.
The claim is not yet reliable because it provides no data, does not explain how the treatment was tested, and relies only on personal testimonials. It also does not show whether there was a control group, peer review, or replication by independent researchers. - 12
Create a short checklist of five questions you could ask to judge whether a scientific claim is reliable.
Think about evidence, methods, replication, bias, and how strong the conclusion is.
A good checklist could ask: What evidence supports the claim? Was the claim tested with a fair method? Can other researchers replicate the result? Are there possible conflicts of interest or sources of bias? Does the conclusion match the strength of the evidence?