No. Plays have stage directions. The director is responsible for interpreting the story, not creating it. If the actions that convince us characters feel what they say they feel aren't in the script, the writer has failed. Read some movie scripts. Characters do and say things that reveal their feelings, rather than proclaiming their feelings as in Shakespeare, and those things are in the script.

And "showing" can be done in dialogue. The first words spoken in the script for "Apocalypse now" are: "It's crazy -- sugar is up to 200 dollars a ton -- sugar!" The fact that the character is talking about sugar prices and war in the same discussion shows you where his true concerns lie.