Why couldn't anybody else write Shakespeare's plays?

Answer 1

Because if they did they wouldn't be Shakespeare's. Many people were writing plays at that time: Shakespeare wrote Shakespeare's plays; Marlowe wrote Marlowe's plays; Jonson wrote Jonson's plays; Middleton wrote Middleton's plays; Webster wrote Webster's plays, and the same for Heywood, and Chettle, and Beaumont and Fletcher.

How do we know that Shakespeare wrote the plays? For three very good reasons:

1. Because they are credited to him in published editions.
2. Because a lot of people said he wrote them at the time.
3. Because nobody at the time suggested that he didn't write them.
   
   

We know now that Shakespeare had help on some of his plays (the published version of one of them officially acknowledges this) just as most other playwrights did. We know also that some poems were credited to Shakespeare which he didn't write, so you can't always go just by the name on the cover. But the name on the cover is corroborated again and again by other references to Shakespeare the playwright and Shakespeare the actor. There is as little reason to believe that someone else wrote everything credited to Shakespeare as there is to believe that the first man on the moon was not really Neil Armstrong but Jerry Garcia.