Re: x*x+1=0
From: David Cressey <david_at_dcressey.com>
Date: Mon, 22 Jan 2001 11:40:24 GMT
Message-ID: <I_Ua6.34761$2X4.74513_at_petpeeve.ziplink.net>
Date: Mon, 22 Jan 2001 11:40:24 GMT
Message-ID: <I_Ua6.34761$2X4.74513_at_petpeeve.ziplink.net>
Jan,
In the preface to the American Edition, it says this:
"What we do in Chapter 11 is extend the concept to Boolean algebras, which means that a valid argument may contain not just three classes of statement, but four: true, false, meaningless, and imaginary. The implications of this, in the fields of logic, philosophy, mathematics, and even physics, are profound."
I note that, in the above, imaginary is listed as the fourth class, while meaningless is listed as third. This might be the answer to your question.
-- Regards, David Cressey www.dcressey.com "Jan Hidders" <hidders_at_REMOVE.THIS.win.tue.nl> wrote in message news:94gv99$c38$2_at_news.tue.nl...Received on Mon Jan 22 2001 - 12:40:24 CET
> Sounds interesting. Do you know what the 4th boolean value was?
>
> --
> Jan Hidders