Either I have just figured out what Shakespeare schollars have spent lifetimes working on, or I read this somewhere and forgot where (there is a name for doing that which Jung invented, "Crypto something").

Here's the key: Shakespeare is writing in a tradition of poetry about morality - virtues and vices - written in anthropomorphic terms. True Feeling introduces Desire to Steady Virtue and they visit Lust. Things like that. He is also writing in the tradition of Dialogs in which a group of philosophers sit around and discuss (in writing) various ethical approaches to things. But Shakespeare makes human characters do the play instead of the virtues and vices, and they act on their ideas unlike the philosophers. Take Othello, for example:

Othello is a play about distinguishing truth from deception, and the tragic end of Othello and everyone around him shows what happens if you can't learn to tell a lie from the truth. The entire play is about this: we open with Iago, the liar, ("I am not what I am" -he says, a reversal of what God says of himself in the bible) explaining to Rodgrego his philosophy of life. Then we learn that Iago is taking money and jewels from Rodgrego and pretending to advance R's love affair with Desdemona. Desdemona has fooled her father into thinking she does not care for Othello, but then she elopes with O and marries him. The father lies to the Magistrate saying that O used magic to seduce Desdemona. D tells the truth and sets that straight. But immediately the assembled leaders of Venice learn the Turks' fleet is sailing for Rhodes - or is this a feint disguising the real point of the attack - Cyprus. How can they tell? That's what the play is about. Finding reality in the midst of false seeming.

Iago goes on to fool his wife, and Casio (who is unfortunately named after a video game company - Just fooling) and in the end murders Rodrego, tries to murder Casio, Othello murders Desdemona,Othello tries to kill Iago, Iago murders his wife, Othello commits suicide - the stage is littered with corpses. Offstage lies D's father, who has died of grief back in Venice. This carnage has been caused due to various characters, most notably Othello, not being able to tell that Iago is lying. In fact one line which is repeated often in the play is that Iago is an honest man (remember Anthony in Julius Caesar "Brutus is an honest man" or words to that great ironic effect).

There you have it. The key to what is happening in the particular play is usually found in the opening scene. Its just that we don't understand that means of organizing drama any longer. Now you do.