I read this as a criticism of something I didn't actually write or intend.
I said there are often multiple meanings, and correct understanding requires knowing that there are multiple valid meanings, and knowing the context enough to select the intended one. Remember, restalis started by complaining that "continent" should not include islands. I pointed out that there are multiple definitions for continent, including widely used ones which include islands.
restalis then argued that the Norse discovered America by reaching western Iceland, which is on the North American plate. Now, I happen to believe that many people discovered America, for different definitions of "discover" and "America". Some definitions are more useful and appropriate than others.
My response was meant to highlight that it's unwise to insist on one of several correct definitions of "continent" then turn around and use a non-standard definition of "discovered America" which is more like "first European to set foot on land on the North American plate." Nor do I think it's a useful definition.
You want to use the more standard definition, which is Euro centric for the reasons you described. I'm also fine with that definition. My point has always been that there are multiple definitions with different cultural contexts. I don't think it makes sense to complain about one usage by pulling it out of a valid context and insisting it must fit into another context.
You seem to have interpreted my counter-example as an insistence that it is the only possible counter-example. I mentioned it because restalis' definition used "North American Plate". I needed something which pre-dated the Norse settlement of Iceland. I realize now that I could have pointed to the the pre-Norse Celtic monks on Iceland, though that just shows that there are multiple objections to restalis' new definition, not that mine is fundamentally wrong.
I think you will have no problems in saying that Leif Erikson and his extended family discovered Newfoundland? Vinland and Markland did affect Norse society on Greenland, and the Norse spread knowledge of it, which we still know about through the sagas and in the Descriptio insularum Aquilonis. By your own definition, the Norse discovered America, yes?
If the Norse did not discover America, when do you think Columbus did? 1492, when he and his crew found some islands and returned to Europe to report? Or the third voyage, when Columbus was at the mouth of the Orinoco and surmised there was a large land mass to be discovered? Or when Amerigo Vespucci demonstrated that it was a new continent, and not part of Asia? I think all three can be applicable moments of discovery.
Even in the scientific literature, discoveries are made multiple times. The Cooley–Tukey algorithm for FFT, for example, was described by Gauss, though his posthumous publication was not influential. In my own field, we use the "Tanimoto similarity" based indirectly on work Tanimoto did in the 1950s, even though "Jaccard index" is the more widely used term and Jaccard published in the 1910s.
History is complicated.
