FOM: What is f.o.m., briefly?

[Matt Insall]

Professor Kanovei said:

> >It is perhaps both possible and impossible

Professor Kanovei next said:

``The first line of my reply is not tautological
(a tautology would be saying "either possible or impossible"
which is not what I wrote).''

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In American politics, your first line is not referred to as a tautology, but
as a ``waffle''.  On the other hand, your first line is always true, in
standard written English, because the word ``perhaps'' removes any
commitment to whatever comes after it.  Generally, the word ``perhaps'' in
English means ``the following is either true or false''.  In symbols:

``A or not(A)'',

where A stands for ``it is both possible and impossible''.  Now, in
classical logic, the statement ``A or not(A)'' is a tautology, but, as we
all know after much discussion in the past, there are several on this list
who consider no logic system to be preferred.  That is fine.  But why not
just be plain about it and say what you mean?  You are using normal English
words to discuss an unusual interpretation of normal English words, without
specifying the formal system of which you intend to speak.


Matt Insall
www.umr.edu/~insall