Too often "no evidence" means "no evidence that I know of" which really means "I don't know". Doctors in particular use "no evidence" this way all the time bec

Too often "no evidence" means "no evidence that I know of" which really means "I don't know". Doctors in particular use "no evidence" this way all the time because they are trained to show confidence in diagnosis when the truth is they often don't know and are just trying things to get some clues. If you suggest something they are not familiar with they'll often say "there's no evidence that works". You have to show them evidence to get them to try it. The evidence may exist, they just don't know about it. Even when it is true that there is no evidence, that often just means no one has actually studied the problem. So "no evidence we can cure the common cold" really means "no one has actually tried to cure the common cold because we consider it too complex a problem so we've never tried". Now that the pandemic has forced a lot of scientists to actually try curing one coronavirus they are actually starting to think maybe they could cure the common cold and the flu and even have some drugs in clinical trials. Curing colds could mean combatting many viruses individually, but that doesn't seem as difficult as mapping the human genome. So what if there are 200 viruses that cause colds? The sooner you start curing them all the sooner colds will be gone. It basically just became dogma so you couldn't get grant funding for it. So another interpretation of "no evidence" is "we haven't tried".