But how many of these can you remember? I currently use almost fifty different passwords. I can't imagine committing fifty different pass phrases to memory.
That's what password managers are for. Just remember the password for the manager, plus maybe one or two critical accounts (e.g. email) and you're good to go. Let the manager deal with the complexity of generating and remembering random passwords.
I don't understand this response? A passphrase is easier to remember than a password. 50 passphrases may not be easy to remember, but they're easier than 50 passwords.