Just to be clear, I'm not trying to say Perl shouldn't be/isn't logical... I'm just pointing out some of the logical concepts that come from English where they're involved.

Also, I tend to think that push having no default to $_ behavior makes sense, partly because it's a binary operator. Since it takes two objects, neither of which is necessarily a scalar, it seems that the sanest way of handling it, in a way that will require the least documentation to understand, is to insist on explicit arguments.