Why is it wrong to make another copy of YOUR copy? It doesn't harm the guy
who gave you the copy in any way. They still have their copy.
Let's extend this to food. Someone came up with a recipe and decided to sell
the food known as potato chips (or crisps if you're British). Is it wrong, if
you know the recipe, to yourself make potato chips because it's not "your"
recipe?
Suggesting that it's wrong to share knowledge that didn't originate from you
goes completely against human nature. Our society only exists because we
share this knowledge.