I'm sure you've all read about the speculation regarding the potential carcinogeny of the radio waves emitted (and received?) by mobile phones.
I assume we're right, that mobile phones are harmless.
But suppose they are harmful, would we know?
How would we know that we would know? If, for example, we are able to say, without the benefit of hindsight, that we would have known asbestos were harmful, or any other substance that was found to have been harmful after decades of usage, then we might have a basis to argue that maybe we would know about phones.
So, would we have known about the harmful effects of asbestos? Would HN have been a pocket of protest and warning about asbestos, or would we have been oblivious about it?
If we would have been oblivious about it, how do we know we're not now similarly oblivious about mobile phones? (No, I'm not saying they are harmful. Either they aren't harmful, or I'm oblivious to the fact that they are if at all they are).
How highly do we rate our ability to be correct?