There is a difference between imitating or appropriating a culture thats not yours, and being influenced by another culture. The first leads to a weak parody of the original culture. The second can lead to a merging and melding of ideas that transcend both cultures to become something unique.
I mostly agree with this, but with the unfortunate caveat that the difference between the two is subjective: I might truly love reggae [Note: I hate reggae. Ed.] and truly be playing it to the best of my ability out of respect, but the listener might see a Scandinavian-American Upper Midwesterner appropriating Jamaican music. A little generosity of spirit is important on all fronts.And without the free flow of cultural influence, our world would be missing much of what makes it beautiful.
That's wisdom. And so to debase it, let me add: inbreeding is gross. This counts for culture, too.