> walk and talk of it and can walk and talk then as far as i'm concerned, its a duck because that is what a duck was expected to do. This doesn't even parse.

> walk and talk of it and can walk and talk then as far as i'm concerned, its a duck because that is what a duck was expected to do. This doesn't even parse. Duck-typing is the idea that an object's type at a particular time is made up of the set of fields and methods it has _at that time_. I suppose that doesn't strictly require updating, but it would be a pretty lame duck with it. Polymorphism w/o inheritance is a fine description. How do you think that can be accomplished without dynamic updating?