what does it mean to say that if a hypothesis is scientific, then there must be a means of proving it wrong.?

Answer 1

Normally, this is stated as proving the negation, not proving it wrong. What is done is to take the hypothesis and state its opposite and then see if can be disproven more easily.
As an example, take the thesis, "Electricity is some times dangerous to humans" the negation would be "Electricity is never dangerous to humans" and that is easy to prove because you only have to find one case where electricity was dangerous/killing to prove it. Usually the negation has to be stated very carefully and the situation is more complicated.
The process actually comes from mathematics where things are more straight forward. There is a famous short essay that includes "How to catch lion: Subtract the set of all things non-lion" which leaves aside the question of how one sorts a real life set of animals.

Answer 2

Just that a scientific hypothesis should predict something. Let me make up an example.

Consider the weather. Two thousand years ago, the patterns of the weather were almost unknown. The people around at the time assumed there must be *some* pattern, so they came up with the hypothesis that some person - a god - was controlling the weather for their own purposes.

How is this weather-god hypothesis different from modern meteorological hypotheses and theories? Well, many things, but one is that it doesn't require *any* specific observations.

Think about it. Does "Zeus throws down thunder when he's angry" tell you what the weather will be like tomorrow? Rain and shine are the same as far as this hypothesis goes - neither would be unexpected, and nothing you can observe tells you which is more likely.

Therefore, no means to prove it wrong. Therefore, unscientific.

Now, *why* must scientific hypotheses be subject to disproof? Well, the most obvious reason is that the hypotheses that are subject to disproof are the ones which are useful - the ones that tell you that it *will* rain tomorrow.

Answer 3

Science predicts. A hypothesis predicts that, given a certain circumstance, then something will happen (for example, if I were to drop a metal wieght and a feather together in a vacuum, they would both fall at the same rate). All hypotheses are susceptible to being misproved through experiment, by showing that on at least one occasion, the predicted outcome didn't occur. If it is impossible to provide a means of misproof, then it is not a hypothesis.

The example I quoted above was 'tried out' on the moon by Armstrong during the first moon landing (the moon has no atmosphere and is practically a vacuum)

Answer 4

It means that it must be testable. I can hypothesize that the grass on my lawn is green because smurfs come out at night and spray paint it green. This is actually scientific because it can be proven wrong. I can leave hidden cameras outside and watch for the smurfs, and I can cut into the blades of grass and see if the color goes beyond the surface.
The cornerstone of science is falsifiability, meaning all theories must come built in with ways to prove them wrong. For example, relativity predicts the bending of starlight in gravity fields. This is a testable prediction and can be proven wrong by watching starlight before the moon or some other large body passes in front of the star, and while the body is in front of the star. The light should be shifted from its expected location and it is. Experiments have verified this and other predictions of relativity.

Answer 5

Here is an example of an bad hypothesis.
The world was magically created 10,000 years ago, but it was created in such a way to make it appear that it was created 4.5 billion years ago.

The problem with this hypothesis is that you can't prove it wrong. According to the hypothesis every measurement and every observation that we make will suggest that the earth is 4.5 billion years old. Then the question is how can we determine if this hypothesis is correct, or if in reality the earth is billions of years old and the stated hypothesis is wrong?