A few things about PHP, Java, and Ruby: PHP, Java, and Ruby are all compiled to byte code before executed. Java and Ruby are strongly typed languages. PHP and Ruby are dynamically typed languages (no explicit variable declarations). Ruby and PHP are compiled when run but Java is compiled ahead of time.

But significant to my point: Ruby classes are created at runtime but PHP and Java classes are created at compile time. This is why you can't, with runtime code, alter the structure of a class in PHP or Java.

Your point about class definitions being frozen is apt — but much of the nomenclature you're using to describe languages is meaningless.

Please read the classic What To Know Before Debating Type Systems: http://cdsmith.wordpress.com/2011/01/09/an-old-article-i-wro...

Not meaningless, just debated. And even then, the web has helped to reduce the confusion around the terms.

http://en.wikipedia.org/wiki/Type_system#Static_typing

That article you linked to is useless. If we just called them alpha, beta, gamma, and delta type systems would a rose by any other name smell sweet?