Why isn't the eigenclass equivalent to self.class, when it looks so similar?

Why isn't the eigenclass equivalent to self.class, when it looks so similar?

ruby language-features eigenclass

ruby

Methods in Ruby: objects or not?

ruby object methods language-features

ruby

Any chances to imitate times() Ruby method in C#?

c# ruby language-features cycle

ruby

Name this python/ruby language construct (using array values to satisfy function parameters)

python ruby syntax language-features

ruby

If monkey patching is permitted in both Ruby and Python, why is it more controversial in Ruby?

python ruby language-features monkeypatching

ruby

equivalent of Python's "with" in Ruby

python ruby language-features with-statement control-flow

ruby

Fixed Object Id for System Objects and Small Integers in Ruby

ruby programming-languages language-design language-features

ruby

What are the features of dynamic languages (like Ruby or Clojure) which you are missing in Scala?

ruby scala clojure language-features dynamic-languages

ruby