Is Your Project Scientifically Testable? Part 2

Go back to part one.

OK, now lets take these statements one by one, to see whether they are scientifically testable.

1. Quartz is harder than calcite.

Yes! Can you test to see whether quartz is harder than calcite? Sure you can! You can use the Mohs hardness scale, testing each mineral to see how resistant it is to being scratched. In fact, both quartz and calcite are reference minerals in the Mohs hardness scale. Quartz has a hardness of 7, while calcite has a hardness of 3, so quartz is harder than calcite. This statement is scientifically testable.
2. Quartz is softer than calcite.

Yes! Can you test this statement? Yes, you can test it in the same way as in #1, by using the Mohs hardness scale. Testing would show that the statement is not correct, but the statement is still testable. Don’t confuse “scientifically testable” with “correct.”
3. Quartz is prettier than calcite.

No. Can you test this statement? Hmm. What device would you use to measure the prettiness of each mineral? We don’t have a “pretty meter” that can measure the relative prettiness of objects.

What about asking a group of people which they think is prettier? As the old saying goes, beauty (or pretty in this case) is in the eye of the beholder. Asking people if they thought quartz was prettier would measure their opinion, not a property of the quartz. This statement is NOT scientifically testable.

4. Many people think that quartz is prettier than calcite.

Yes! Is this statement scientifically testable? How would you test it? Get a group of people and ask them if they think that quartz is prettier. While this statement seems very similar to the previous statement, it is very different, and this one is testable. Look at these two statements carefully, and be sure that you understand the difference between the two.
5. Quartz is denser than calcite.

Yes! Is this statement scientifically testable? You measure density by measuring the weight and volume of an object. You could determine the density of a variety of quartz specimens and compare that to the density of a variety of specimens of calcite. What you would find is that all specimens of quartz, from grains of sand to boulders, have a density of about 2.65 grams per cubic centimeter, while specimens of the mineral calcite have a density of about 2.71 grams per cubic centimeter. Here again, the statement is false (calcite is denser) but the statement is still scientifically testable.
6. Quartz is more valuable than calcite.

No. What about this one? Is it scientifically testable? How do you determine the value of something? Value for both quartz and calcite depends on the size of the specimens, the quality of the specimens, who wants them and how much they want each. Value is a personal opinion, not a fixed property, so it is NOT scientifically testable.

As with the example about prettiness, you could test to see which mineral people think is most valuable, but again that is a very different statement.

7. Quartz attracts more unicorns than calcite.

Yes! OK, how would you test this one? Simple. Put several piles of quartz on one side of your yard or some other suitable unicorn habitat, and several piles of calcite on the other side. Then count the number of unicorns that are attracted to each. The answer for both will probably be zero, but the statement is still scientifically testable. A statement does not have to be realistic to be testable.
8. Quartz attracts more invisible, undetectable unicorns than calcite.

No. Is this statement scientifically testable? If there is no way to detect the unicorns, there is no way to know whether they are there or not. That means that there is no way to perform scientific tests, so even if there is such a thing as invisible, undetectable unicorns, this statement is NOT testable.

So, to determine if your hypothesis is scientifically testable, the first thing to do is to read that hypothesis very carefully. Ask yourself what test could be done that would provide scientific evidence for or against that statement. If there is not a test that will provide that evidence, then your hypothesis is not testable. Be especially careful when dealing with statements that depend on what people think about something instead of relying on measurable properties.