Jani Hartikainen has followed up on a post from David Otten about standard classes in PHP and how they provide the base for much of what the language does.

David Otton posted a short but thought-provoking post about stdClass, which many think is the "base class" all PHP classes automatically inherit from. I have to admit that I had this misconception as well. [...] This [difference in PHP from other OOP languages] presents some room for analysis in how things are handled in dynamic and static languages, and how those differences affect things...

Jani talks about dynamic and static typing in languages and how that effects the base types things are extended from as well as some of the benefits that having a standard base class affords developers.