> Instances may be Strongly typed in Ruby. Methods are not.

Sure they are, just not all of them:

    [].first('wat') # => TypeError: no implicit conversion of String into Integer

What Ruby lacks is _static typing_ and compile time checks of these types. Instead we have runtime checks in a few places.

> Prefer Composition over Inheritance right? But what if through Composition you > effectively lost all your Type information? That's the issue Ruby presents.

This is mainly advocated because subclassing core classes (e.g. Array) can lead to weird behaviour. For example:

    class MyArray < Array
    end

    m = MyArray.new([10, 20, 30])

    p m.map { |number| number * 2 }.class # => Array

Here one would probably expect an instance of MyArray to be returned, but instead we get a vanilla Array.