The Ship of Theseus is a philosophical challenge that posits the following question - if something has had all of its original parts replaced, is it still the same thing? Or is it something else entirely?
This theory also applies to Trigger's broom from that episode of Only Fools and Horses and, as it turns out, rock bands.
Whilst they may have carried the same name for their entire existence, there are plenty of famous groups that have chopped and changed so many times that there are no founding members left. And yet, they still continue to carry the same lineage as the band that started it all. Is this fair? Is it morally right? Does anybody really care? Probably not.
Still, it makes for an interesting read (hopefully), but it's also a murky subject with plenty of rules and regulations to go over.
An "original member", for the purposes of this list, is one who was present during the first full iteration of the band. They don't necessarily have to have played on all of the band's records, they just had to have been there right at the start.
Opeth are a progressive metal band from Sweden, which seems to produce slightly alternative metal at an alarming rate. If they could somehow harness it as a fuel source, then all of their energy concerns would be gone forever.
The group were formed in 1990 by vocalist David Isberg, who pulled together a gang of fellow musicians that he knew from his time on the scene. When things weren't working out, Isberg recruited the guitarist Mikael Åkerfeldt to serve as the band's new bassist.
There was just one problem - Isberg hadn't told the original bassist that he was being replaced. Whoops.
This resulted in a massive falling out between Isberg and the other members, all of whom walked out on Opeth, leaving just he and Åkerfeldt behind. Whilst Åkerfeldt has stuck around since that day, Isberg bailed after just two years, handing the vocal reigns over to his buddy in the process.
And just how did Opeth fair following Isberg's departure? Well, they've released 13 studio albums, many of which routinely appear in the Billboard charts over in America.
So, yeah, they managed just fine.