How to Approach Textual Critique of Shakespeare's Plays

In 1623 seven years after his death Shakespeare dies in 1616 two of the actors from the Kingsmen Shakespeare's company collect together the complete dramatic works of Shakespeare. So 36 plays are published together in this folio of 1623 and that includes 18 which have not previously been published. In their epistle to the readers they tell us that they've collected all the plays together as where before you were abused with diverse stolen and surreptitious copies maimed and deformed by the frauds and stealths of injurious impostors even those are now offered to your view cured and perfect of their limbs. It's clear that what Hemming and Condell are getting out here is