FOM: Hintikka on branching quantifiers in mathematics - IF logic

Jeffrey Ketland ketland at
Fri Mar 16 12:09:09 EST 2001

For an adventurous book discussing logic with branching quantifiers in the
context of formalizing *mathematics*, see:

[1] Hintikka, Jaakko 1996: _The Principles of Mathematics Revisited_. CUP.

Hintikka calls his logic "independence-friendly logic" (IF logic) - he
claims that it is *first-order*!
Oddly enough, the term "branching quantifiers" doesn't appear in the index,
but the ideas are the same--skolem functions, etc. In fact, a branching
quantifer formula appears on p. 50.

There's an excellent review of Hintikka's book in Mind couple of years back:

[2] Velleman, Daniel J. 1999: _Review of Hintikka 1996_. Mind 108 (Jan
1999), pp. 170-179.

Velleman finishes with a Quinian quip: "In my opinion, IF logic is merely
second-order logic in sheep's clothing".

Best - Jeff

~~~~~~~~~~~ Jeffrey Ketland ~~~~~~~~~
Dept of Philosophy, University of Nottingham
Nottingham NG7 2RD United Kingdom
Tel: 0115 951 5843
Home: 0115 922 3978
E-mail: jeffrey.ketland at
Home: ketland at

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