That is correct, and it is important. A classic example of this was when someone asked J. B. S. Haldane: What would disprove evolution? He said, "fossil rabbits in the Precambrian." That does not mean anyone expects find fossil rabbits in Precambrian rocks. As far as anyone knows, that is impossible. However, if rabbits were found it would disprove much of evolutionary theory. It is a logical assertion, not an assertion about what is likely to happen, or what can happen.
Cold fusion is predicated on calorimetry, which in turn is based on the second law of thermodynamics. The only way you can disprove cold fusion is to show that heat can of itself pass from a cooler body to a hotter body. Hypothetically, someone might devise an experiment that does this, but you will not find a single physicist or chemist who thinks that that could happen. As a practical matter, the second law is irrefutable, and that makes cold fusion irrefutable.
To put it another way, THHuxleynew has to prove that every major type of calorimetry, including isoperibolic, phase change, temperature based, flow and Seebeck does not work. Or they have worked in millions of experiments over the last 250 years, but for unknown reasons they failed in thousands of cold fusion experiments done by world class experts. His hypothesis is that these experts made thousands of mistakes for 30 years. There is not a single valid example of excess heat. Yet no skeptic, including THHuxleynew himself, has ever found one of these errors. If there was even one valid experiment, that would prove cold fusion exists, and the other 9,999 mistakes would not disprove anything. So the skeptics must show that every single published positive experiment is wrong. Of course the other 9,999 are not wrong! If hundreds of experts could make undetected, unknown errors using 250-year-old techniques, experimental science itself would not work. We would still be living in caves. It is astounding that any scientist believes such nonsense.
