That is my point, it is absurd to make claims about what cannot be measured as if they are knowledge. If there is X thing or phenomena, and it does exist but cannot be detected, it is absurd to say it exists or does not exist, it is utterly meaningless, just like X-rays were hundreds of years ago. As far as humanity was concerned with knowledge they did not exist back then in any informational context. Thus their existence at the time when they could not be detected was not truth at the time, because they could not be detected, though it is true they existed then, but we only know that from today's measurements.

I think truth only exists in the context of standardization and is otherwise a meaningless word. A weight is truth, it is measurable. An experience of that weight is also true. However to make a claim about knowing a weight without having ever measured it, to have an opinion on how much something weighs without detecting it is not truth, even if the opinion is a guess that is entirely accurate.

This is of course my opinion and nothing more than that.