EUFSLAT award to Petr Ha

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EUFSLAT award to Petr Hajek

• It is a pleasure for me to be here and to have
  the possibility to say some words about Petr
  Hajek.
• For me and for many other people, he is not only
  a great scientist, but also a teacher and a
  friend.
• Each of us could tell a lot of stories about Petr
  motivating his great personality.
• But at this moment we are celebrating him as a
  scientist, and hence we will mainly speak about
  his scientific activity.

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Petrs scientific activity

• Before speaking about fuzzy logic, which in the
  last two decades has become Petrs main research
  field, let me recall that his activity is by no
  means limited to fuzzy logic.
• Petr wrote an important book with Vopenka about
  the theory of semisets. Then he greatly
  contributed to the metamathematics of arithmetic
  and wrote another important book with Pudlak.

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Petrs scientific activity

• At the same time, he did a great work about the
  applications (see the GUHA method).
• Petrs work on Fuzzy Logic is a good compromise
  between mathematical abstract theory and
  applications.
• In his book Metamathematics of Fuzzy Logic, Petr
  takes into account both aspects
• he provides for a mathematical apparatus for
  fuzzy logic, thus considering problems like
  completeness, standard completeness,
  decidability, Co-NP completeness etc.

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Petrs work on Fuzzy Logic

• Moreover he invented an important new fuzzy
  logic, namely, BL, which will probably be called
  H (Hajeks logic) moreover he prepared the
  ground for the birth of other even weaker logics
  (the so called flea logics).
• But at the same time he does not study fuzzy
  logic in itself, but he is interested in its
  applications. For instance, logics with constants
  for truth degrees, fuzzy logics of probability,
  of possibility and of belief, fuzzy modal logics,
  fuzzy description logics.

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The reasons for Petrs success

• Petr Hajek is certainly a bright sceintist, but
  he is not the only good scientist in Logic or in
  Mathematics.
• So, we may ask what are the reasons for his
  success? (Remember for instance that his book has
  a lot of citations).
• I think that a peculiarity of Petr is his ability
  to attract both abstract mathematicians and
  applied scientists.
• Abstract mathematicians are not enthousiastic
  about applications when such applications do not
  involve enough mathematics.

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The reasons for Petrs success

• On the other hand, applied researcher are
  skeptical about abstract results when do not see
  applications.
• Well, Petr showed that even applications may have
  an interesting mathematical theory, and hence may
  be attractive also for a pure mathematician.
• At the same time mathematics may be very useful
  in the applications, and hence it may attract
  applied researchers.

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Conclusions

• Summing-up, I completely agree with the choice of
  Petr Hajek for the EUFSLAT award.
• Let me add that we are preparing a volume for
  Trends in Logic, outstanding contributions, which
  will be devoted to Petr Hàjek and his
  contribution to Mathematical Fuzzy Logic (a new
  research field, of which Petr is probably the
  leader).
• The volume is taking long, mostly due to my
  inefficiency, but I now think that we are close
  to the end.
• The goal of the volume is to show to the
  mathematical community that Petrs work will be
  continued.

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Conclusions

• But of course, the real conclusion is
• THANK YOU, Petr, for your work, and
  congratulations for the EUFSLAT award.