I found a short piece for the blog. This is the introduction to my old Chapter 5, from a book on Nietzsche and Logic. This piece reviews some of the nonsense postmodernists say about logic.
Nietzsche on Logic
This chapter responds to a handful of postmodern tales
about Nietzsche’s alleged animosity toward logic. It compares those claims with the text,
demonstrates that they are mistaken, and argues for four theses.
The four theses are 1) that Nietzsche clearly values
and respects logic, but is suspicious about what he calls its presuppositions,
2) that he describes moral vices which he associates with logic, 3) that he
describes a fallacy which he associates with justifications for very general
propositions (possibly including propositions of logic), and 4) that many of
the critical remarks which readers might easily assume are aimed at logic are
in fact aimed at other things, usually one of two things: that faith he
describes as being presupposed by logic in 1) above, or else those vices he
associates with logic in 2) above.
I propose to counter postmodern mistakes by relying on
the power of careful reading. If we
separate Nietzsche’s remarks about logic from his remarks about other things –
such as metaphysics, biology, history, ethics – we can finally isolate his
respect for logic on one side of the table, and a small collection of likely
sources of the century old rumor that he devalues or disrespects it on the
other.
Postmodernists are not the first writers to claim that
Nietzsche held logic in low esteem, although theirs is surely the first school
to make that opinion orthodox. In sharp
contrast to their view, Nietzsche’s published works praise and urge us to study
logic. I am not the first to make this
point. Hales and Welshon noted
Nietzsche’s positive regard for logic while also arguing that his position
appears to be that logic, like language, can be misleading. ‘The charge that logic or language is
misleading’, they add, ‘is ultimately a criticism of those who are thereby
misled and is not an objection that undermines logic as a science of thought or
as a formal representation of natural language’ (2000, 55). They are right, but Nietzsche never published
the statement that logic is misleading.
In fact, as we shall see, he rarely talked about the science of
logic. He was much more likely to talk
about the use of logic than about the science.
He was also more likely to talk about an organic capacity that he called
logic than about the science of logic.
Another thing he
never did is to devalue or disparage the elements of logic. As Robert Nola discovered,
Nietzsche does not
criticise any principles of logic. In
fact, he often employs them, for example when he says that, owing to Boscovich,
‘materialistic atomism is one of the best refuted theories there is’
([BGE 12] italics added). All refutation
involves at least the principle known as Modus Tollens. And a little further on he takes himself to
have advanced an argument which is, as he says, a ‘reductio ad absurdam’
[BGE 15]; and again he says that the concept of a causa sui is a ‘rape
and perversion of logic’ [BGE 21]. If
the principles of logic are not abandoned and are used and even praised, then
what is Nietzsche’s criticism of logic?
The attack is more upon what he takes to be the presuppositions, or
theory of the status, of logic, and not the principles themselves. (2003, 491)
Nola writes that Nietzsche’s ‘attack is more upon’
presuppositions than principles, but it is not really a matter of more or
less. Nietzsche never attacks principles
of logic. His works, like most works in
philosophy, never bring even one of the parts of logic into
focus. Like nearly all philosophers, he
was interested in other matters. In
particular, he was interested in what he called ‘historical philosophy’. It is this historical mode of philosophizing
which prompts the question, in his first published aphorism, as to how logic
arises from unlogic (HH 1). As a
philosopher, Nietzsche wants to account for logic within a larger account of
human development, including human cognitive development (HH 2). As a writer and thinker, he wants to use
it. Like most philosophers, he has
little or no reason to focus on or theorize it.
In order to introduce to our discussion a first example
of a logic-disrespecting Nietzsche of the postmodern variety, let us turn to
page 3 of Nietzsche and Metaphysics, where Michael Haar claims that ‘the
specific nature of Nietzsche’s discourse might well be defined in the first
instance as an attempt to encourage disbelief in the laws of logic and the
rules of grammar’ (1996, 3). As a
companion to Haar’s Nietzsche, consider these words from David Allison:
The vibrant
expressiveness of Nietzsche’s prose, the fertility and suggestiveness of its
content, refuse to be systematized; it resists the imposition of static
categories, of rule governance – whether logical or linguistic. The dynamic flow of the experienced events he
evokes cannot be easily overlooked: it bears no simple definition, it claims no
essence or distinctive form. In this
respect, Nietzsche’s discourse declines reliance upon strict definition, upon
the single, unchanging, univocal meaning of a term, upon the rigorous logical
argument, and most forcefully, upon the principle of identity, which certifies
that one thing is only one thing – and nothing else. Nietzsche turns away from all of this on the
level of style, toward the more poetic, figurative use of
language: the aphorism, the apothegm, the image, the simile, the metaphor, all
of which are essentially unstable, imbalanced means of expression. (2001, 75f)
Allison’s Nietzsche rebels against ‘rule governance,’
‘rigorous logical argument’, ‘univocal meaning’, ‘static categories’ and ‘the
principle of identity’.
Haar’s Nietzsche, who is seditious against ‘grammar’
and the ‘laws of logic’ in general, also goes on to punch at ‘the principle of
identity’ in particular. Nietzsche’s
‘key words … elude conceptual logic’ and ‘are meant to subvert, fracture and dismiss
concepts’, Haar claims. ‘Whereas a concept, in the classical sense, comprises
and contains, in an identical and total manner, the content that it assumes,
most of Nietzsche’s key words bring forth, as we shall see, a plurality of
meanings undermining any logic based on the principle of identity’ (1996,
3). So, both Haar and Allison describe a
Nietzsche who has a negative relationship with ‘the principle of
identity’.
Haar’s
belief about the potential of words used with ‘a plurality of meanings’ to
undermine something in logic deserves special attention. A similar claim is made by Louise Mabille in Nietzsche
and the Anglo-Saxon Tradition.
In Nietzsche’s work,
abundant imagery is a deliberate deconstructive strategy. The richness of his imagery and the many
contradictions engendered thereby, prevents him from being included in a
system, and subverts logic as the foundation for philosophy itself. For Nietzsche, logic is just another
structure that developed in intellectual history, whose genealogy can be
given. This genealogy makes it clear
that logic itself arose from a rhetorical peremptory sentence, and is
ultimately aimed at establishing and maintaining relations of power. (2009, 141)
Mabille believes that using imagery subverts logic, and
perhaps that contradictions subvert logic, and perhaps that not being in a
system subverts logic. By ‘imagery’ she
means a kind of word or words.
Meanwhile, Haar talks about terms with ‘a plurality of meanings’, by
which he means a kind of word or words. Thus, both Haar and Mabile appear to believe
that using a particular kind of phrasing could subvert logic, which is false,
because whatever phrasing one uses, logic just assigns a variable, either to
that phrasing or to the proposition in which it appears, as it does with all
other terms and phrases. Words conveying
imagery pose no special challenge. Nor
do words with ‘a plurality of meanings.’
Meanwhile, a contradiction is something described by
logic. It is also something that
violates a rule of logic. But the mere
fact that something violates a rule of logic cannot subvert logic. If violating a rule subverted the body of
which that rule is a member, then 3+5=9, which violates at least one rule of
arithmetic, would subvert arithmetic.
Violating a rule of math or logic does not affect the individual rule
violated, nor does it affect the body of elements of which that rule is a
part. If anything, an instance of 3+5=9
in the world validates and strengthens the rules of arithmetic when the rules
are used to call it out as and prove it to be an error, and thus demonstrate
their usefulness. The same goes for
contradictions; detecting them depends upon and demonstrates the usefulness of
logic. If Mabille, or any of us, can
recognize a contradiction, then logic is to thank, not to mourn. And if it is true that imagery often
engenders contradictions, logic would be crucial to our knowing it. Meanwhile, explaining what it means to be
prevented from ‘being included in a system’ will require some use of logic. Lastly, a text that is unsystematizable has
at least one thing in common with a text that is rife with contradictions,
imagery, and uses invoking a plurality of meanings, in that all such texts can
subvert or undermine logic about as much as they can subvert or undermine the
moon.
A fourth and final sample of this genre comes from Nietzsche’s
Philosophy of Science by Babette E. Babich.
The goal and rule of
valid logical argument is its conservative assurance of truth (justification),
if truth is to be had. Only where the
premises are given as true to begin with may one validly proceed to (similarly
true) conclusions. The logical effort is
necessarily tautological: it assumes truth to preserve it.
But
if there is no truth, only interpretation, then anything can be concluded from
whatever is ordinarily taken to be true.
Hence Nietzsche’s fascination with the Assassin’s motto, “Nothing is
true: everything is allowed,” does not blindly presume the principles of
ordinary logic but is rather concinnously employed. For the benefit of believers in ordinary
logic, A and –A can be posited as equivalent.
If it is false that nothing is true or false, anything follows. The value of truth is elided in the
ambivalence of insistent contradiction.
This notional dissonance is characterized by the fluid terms,
contradictions, aphorisms, metaphors, hyperbole, and the tropings and the
concinnous invocations and so on making up the conceptual challenge of
Nietzsche’s style. (1994, 112)
This passage is deeply confused.[i] When Babich speaks ‘for the benefit of
believers in ordinary logic’, is she talking down to someone? Does she think there is a logic other than
ordinary logic? Is there a vein of
discourse that urges disbelief in ‘ordinary logic’ in favor of that other
logic? The answers to all three
questions are affirmative. I discuss
postmodern myths about the existence of a counter-logic, and attempts to
associate Nietzsche with it, in Chapter 7 below.
Meanwhile,
‘A and –A can be posited as equivalent,’ claims Babich. What does that mean? As long as ‘equivalent’ allows for ‘having
the same truth value’, and the symbols she employs are given standard
interpretations in propositional logic, she would be saying that a proposition
and its denial can both be true, which violates the law of non-contradiction;
and that they can both be false, which also violates it.
Babich
describes a Nietzsche who denies the law of non-contradiction, while Allison
and Haar think that he rejected the law of identity. There are three laws, or law-like statements,
traditionally discussed in this area.
They are the law of identity, the law of non-contradiction and the law
of excluded middle. In Nietzsche’s
Perspectivism, Hales and Welshon discuss several postmodern theorists who
argue that Nietzsche rejected the law of excluded middle, including Derrida
(2000, 51f). So, for each of the three
traditional laws, there is at least one postmodernist who has associated
Nietzsche with its denial.
In addition, all of the postmodernists cited above hold
that Nietzsche’s written style somehow reflects or embodies his attitude toward
logic.
Are these authors right? Does Nietzsche urge us to resist the rules of
logic? Does he decline to rely on
rigorous arguments? Does he resist ‘rule
governance’? Does he deny the law of
identity? Does he deny the law of
excluded middle? Does he deny the law of
non-contradiction? If he does not deny
these law-like statements, does he downgrade their scope or status? Finally, is Nietzsche’s style a turning away
from, or even a rebuke to logic?
To each of these questions my answer is no. I will defend each answer separately. ...
The
differences between Haar, Allison, Mabille and Babich, along with the theorists
described by Hales and Welshon, exemplify the variety to be found among
postmodernists who hold the view that Nietzsche rebels against logic. What each theorist describes, however, is a
type of rebellion characteristic of postmodern philosophy. None of it can be found in Nietzsche.
[i] Babich’s second sentence above is false because we
can hypothesize or assume or imagine a proposition’s truth, and thus we need
not start from ‘given’ truths in order
to use logic. The third sentence speaks
of ‘the logical effort’ without defining it.
Logicians will agree, however, that efforts are not propositional, and
thus cannot be tautological. Against the
fourth sentence: ‘interpretation’ saves enough of ‘truth’ to prevent the
consequence Babich sees. Against the
seventh sentence, ‘If it is false that nothing is true or false’, then it is
true that something is, and it is not the case that just anything follows from
that. What Babich meant to say was that
if it is true that nothing is true or false, anything follows. But of course, that premise is more
obviously contradictory than hers.
