Rykov's Q

["Vladimir Rykov, PhD in Computational Linguistics, MOCKBA" <rykov2000@mail.ru>]

My Qs

~V

                               ANDRZEJ!

     I think  about  MIZAR.  Strangely but it seems few mathematicians
know about it.  I hope I am wrong.  The advantage of your idea is that
it is  natural.  The  math notation (all these "E back" or "A up") are
almost pre-MIZAR. Somebody had to make this step.

     I hope - now my Qs will  be  more  techniacal  and  maybe  you'll
answer just with a little phrase.

     1.SUBSET_1:4 Does this mean that for every set X Emptyset is subset
of X?

     2.Has set E there has any spec meaning?  Maybe  I  miss  it  some
where?

     3. The  operator  "minus  with  dots  up  and  down"  (I  call it
"symmetric difference") in SUBSET_1:18.  I met it in  BOOLE.  Does  it
mean the same? If yes why it is redefined?

     4. I'd like to ask you about TARSKI Def 4.  I still can not get -
the U applied to the only set X.  Does it modify  it  or  reveals  any
hidden property?  I  understand  it  that  this operation "lowers" the
level of U X to X (in the sense of "stratification"  as  you  said  me
before) so that ... ex Y ... etc

     I am sorry - you may answer any time.  Still - as I said Math and
esp Logic demands exact understanding.



     Vladimir