The problem is how precisely do we actually know and that is where the uncertainty comes in. If someone gives you a pound of Gold and a pound of rice. I think that I can confidently say that the pound of rice will be accurate to within an ounce and that the pound of Gold will be an accurate measurement within tenths of Grams. The problem is that we don't have a precise measurement of mass, we can only measure it to 10 digits, give or take a few.
It turns out that there is a level of uncertainty to everything, nothing can be known to an arbitrarily precise number. It turns out that things like Plank's constant set an absolute limit on what can be known. It is a very, very small limit I will grant you, but a lot of very small uncertainties do add up : )
Agreed LeGrande. And very well put! Thank you ever so much for your observation!
“It turns out that there is a level of uncertainty to everything, nothing can be known to an arbitrarily precise number.”
You are confusing measurement (an arbitrary mathematical exercise) with counting, which is always certain and absolute. Only discrete existents can be counted. If I want to know how many eggs I have left in the carton, I simply open the carton and count them. If I count six, I know I have six eggs, absolutely and with no uncertainty.
Measurement can never be certain because the units are not discrete existents, but some arbitrary “unit of measure,” which whatever you are measuring may or may not be dimensionally commensurable with. With measurement, it is always, “as precise as needed.”
Within that limit, however, it is real and certain knowledge. Certain enough to be able to perform eye surgery or fly men to the moon.
Hank