Can a Negative Claim Ever Be Proven?

[DaveC426913]

I do not understand what is unreasonable about it. I am fairly certain that scientists have not access to the universe as a whole and only make observations of small parts of it in order to draw conclusions about the nature of the whole.

They don't draw conclusions, but they do make working assumptions and extrapolate.

But you cannot extrapolate to show something does or doesn't exist.

 

[JoeDawg]

make observations of small parts of it in order to draw conclusions about the nature of the whole.

Making predictions about unobserved phenomena, based on observed phenomena is inductive reasoning. It is not the same as direct observation, whether it uses direct observation as basis or not.

Science involves prediction based on evidence; inductive reasoning.
It is not pure observation.

You cannot 'prove' something with induction, like you can with deduction.
http://en.wikipedia.org/wiki/Problem_of_induction

Even observations can be faulty and lead to error.

You cannot 'prove' that something doesn't exist, simply by saying you've never seen it.
You cannot 'prove' that something unseen exists based on what you can see.

You can make all kinds of assumptions, predictions, and inferences, but that is not proof.