Dart's interesting enough if I can actually use it for both Fuchsia and Web [1], but I find the following statement misleading: "Dart’s type system, like the type systems in Java and C#, is sound [2]." Java's type system is not sound [3], nor is C Octothorp's [4]. What gives?

[1] Though what happened with Chrome is a shame: https://news.dartlang.org/2015/03/dart-for-entire-web.html

[2] https://www.dartlang.org/guides/language/sound-dart#what-is-...

[3] https://dev.to/rosstate/java-is-unsound-the-industry-perspec...

[4] https://stackoverflow.com/a/23968075/775282