Difference between Scala's existential types and Java's wildcard by example?

Question

A bit more specific than Stack Overflow question What is an existential type?, what is the difference between Scala\'s existential types and Java\'s wi

Answer 1

The List[_] notation (which as other answers point out is a more powerful analog to Java's List[?]) is a degenerate case of the more general notion of an existential type in Scala.