The Absent Minded Professor

Hello, tech support.

Hello, this is Professor Turnwell on the main campus. I'm having a problem with my email.

What kind of problem, Professor?

My password isn't working.

Okay, we'll change it for you. Since today is Monday, why don't we use monday as your new password.

Fine.

Hello, tech support.

Hello. Professor Turnwell again. You just fixed my password problem yesterday and it's started up all over again.

It isn't working?

No. It isn't.

When you type it in, make sure it is all lower case. What did you type?

I typed in 'tuesday'.

Tuesday? I thought your new password was 'monday'?

Well, that was yesterday. I thought we were following the days of the week.