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Commentary on Husserl's Logical Investigations, Prolegomena Chapter 5

By Jeremy Hausotter


Chapter 5: Psychological Interpretations of Basic Logical Principles

§25 The law of contradiction in the psychologistic interpretation of Mill and Spencer

Husserl begins chapter 5 with some general observations. Psychologism, as demonstrated in the previous chapter, leads to asserting that logic is not a priori nor exact, but vague probabilities dependent upon experience and induction, and are concerned with mental facts (p. 111). The task now is understanding what is the psychological interpretation of logical laws and Husserl examines its application to the law of noncontradiction. Husserl takes JS Mill as an authoritative voice for this view and begins his investigation with Mill.

Mill teaches that the foundation for the law of noncontradiction is the “fact ‘that belief and disbelief are two different mental states’ ” (p. 112). The veracity of this statement is the observation that in our minds that there is a distinct positive phenomenon and its negative, eg. light is opposed by darkness and sound by silence. The law of noncontradiction is hence the generalization of this observation of our minds.

Husserl has some hilarious jabs in this chapter. Concerning this view of Mill’s, he wrote: “Where the fundamental principles of his empiricism prejudices are at stake, all the gods seem to abandon Mill’s otherwise keen intelligence.” (ibid). The reason for this is simple: the opposition between light and darkness, and sound and silence, are not logical laws nor contradictory propositions. Mill’s reasoning for grounding the law of noncontradiction is that

the absolutely constant law... that the appearance of any positive mode of consciousness cannot occur without excluding a correlative negative mode: and that the negative mode cannot occur without excluding the correlative positive mode.” (ibid).

Husserl pointed out that this statement is a tautology, because the opposition between positive and negative requires the concept of mutual exclusion by definition; and since this is a tautology, it tells us nothing.

The law of noncontradiction, on the other hand, cannot be a mere tautology. Contradiction is not defined by stating that propositions are mutually exclusive. Husserl also pointed out that simply because two propositions are mutually exclusive, this does not require them to be contradictory. Some proposition and its negation is contradictory and mutually exclusive, but the opposition between light and darkness does not invoke contradiction while still being mutually exclusive.

The psychologist interpretation of the law of noncontradiction requires interpreting this law as an incompatibility within our belief. Hence the psychologistic interpretation of the law of noncontradiction requires interpreting the impossibility that two contradictory propositions can be true as an incompatibility in one’s judgment. Rather, this impossibility of contradictory propositions has its source in what is ideal, meaning that interpreting it as the incompatibility of judgment acts interprets this impossibility as something real and not ideal.

One final observation to make is an interesting sentence of Husserl’s immediately after his jab at Mill. He wrote: “Only one thing is hard to understand: how such a doctrine could have seemed persuasive.” (p. 112). I wonder if this sentence is autobiographical, where Husserl is looking back 10-15 years ago when he not only held psychologism but advocated for it in his Philosophy of Arithmetic.

§26 Mill’s psychological interpretation of the principle yields no law, but a wholly vague, scientifically unproven empirical proposition

The psychologistic interpretation of the law of noncontradiction can hence be interpreted as “Two contradictorily opposed acts of belief cannot coexist.” (p. 113). At the beginning of section 26 here, Husserl highlights the absurdity of this view with a series of questions and observations.

We would have to ask ourselves what are the conditions and circumstances for this to be true, and somehow judge as to why people believe contradictory beliefs. Some believe abortion is gravely evil, others that it is an invaluable good. How are we to judge between these two opposing views? How are we to also judge those who accept fallacies and derive contradictories from them and still give these views their assent? How are we to handle the problem of the insane person, or those who are delirious, hypnotized, or even animals? Animals are psychological beings, so do they also possess the law of noncontradiction? As it stands, there are many absurdities which arise from the psychologistic view.

One can reply to these that only those humans who possess a normal psychological constitution possess the law of noncontradiction, but then we must raise the question what is meant by “normal”? This would have to be established psychologically. This brings us back to a point Husserl made earlier, namely, that psychologistic laws are vague, inexact, whereas the laws of logic are exact. We cannot derive exact laws from vague ones. Logical laws in the psychologist view are hence reduced to a blind mechanism of psychological association with no further justification than prejudice. Whatever answer the psychologist responds with to Husserl’s objections, one can always reply that the defining principle for normality and as the basis of logic requires a fuzzy, vague view of logic as a science that eliminates its character of strictness and exactitude.

The law of noncontradiction is not a mere statement about the subject and his or her experiences of belief; rather, it is a statement about two states of affairs which cannot both coexist independent of the subject and time, holding absolutely and strictly as a judgment of truth. The law of noncontradiction is concerned about the truth content of propositions. Its psychologistic interpretation is a statement about the psychologistic constitution of man. If man's psychology were different, then on the psychologistic view could not even the law of noncontradiction be invalid?

Appendix to the last two sections

The theme of the appendix is the claim that “empiricism and psychologism are intimately linked.” (p. 115). Husserl claims that empiricism is a skepticism (which he states in footnote one that he will develop this claim in chapter 7). Extreme empiricism is as absurd as extreme skepticism. Both theories destroy “the possibility of the rational justification of mediate knowledge…” (ibid), where by mediate knowledge what is meant is those which arise through inductive experience, i.e. laws of physics, psychology, chemistry, etc. This means then that both empiricism and skepticism are self-defeating, that is, self-referentially inconsistent because these theories “destroys its own possibility as a scientifically proven theory.” (ibid). If empiricism cannot justify mediate knowledge, then it cannot justify its own claims that all knowledge is obtained through inductive experience, and hence is self-defeating.

The reasons for this self-defeat are obvious. If the principles by which we validate an argument are all products of mediate knowledge, then the entire procedure of validating an argument must either result in an infinite regress or circularity. The principles in a proof require justification. If the principles justifying those principles used in the proof are the same, then circularity arises, otherwise, maintaining their difference invokes an infinite regress since the principles justifying the principles in the proof must likewise be themselves justified, and so on.

This problem of circularity or infinite regress brings us to the insight that mediate knowledge requires “ultimate principles on which all proof in the last instance rests.” (p. 116). If we are to avoid the problems of empiricism with its self-referential inconsistency, circularity and infinite regress, there must be first principles of logic upon which we can validate arguments and proofs. These first principles must be immediately evident and self-illuminating. “All principles  which justify possible proofs must therefore be deductively inferrible from certain last, immediately evident principles, so that even the principles of the deduction in question all themselves occur among such principles.” (ibid).

Husserl hence concluded that “extreme empiricism, therefore, since it only basically puts full trust in singular judgments of experience… eo ipso abandons all hope of rationally justifying mediate knowledge.” (ibid). As Husserl observed, this trust is an uncritical one, for it simply ignores the problems that arise from these singular judgments (such as illusions, dreams, hallucinations and Geach’s criticisms of the justified true belief view of epistemology).

Empiricism hence comes at a cost of being prejudiced, for the empiricist will not acknowledge these ultimate, first principles that are immediate insights and given truths, but will instead attempt to explain away these “experiences” of these immediate insights in terms of mediate knowledge, experience, and induction. The first principles must be derived from inductive experience, but this raises the question as to what justifies such principles of derivation?

The inability of the empiricist to justify his principles of derivation, for deriving the first principles from inductive experience brings us to Husserl’s conclusion: extreme empiricism cannot justify its own principles and hence it “is without rational foundation, is, in fact, a mere assumption, no more than a common prejudice.” (ibid).

Extreme empiricism is a psychologism which confuses the psychological origin of judgments in experience with a justification of the same judgment. This is going to be a theme taken up in the next chapter.

An obvious question at this point is what about moderate empiricism such as Hume’s? Husserl concludes that moderate empiricism shares the same fate as extreme empiricism. What made Hume’s empiricism moderate was his attempt to retain a pure mathematics and logic with a priori justification. The natural sciences, on the other hand, are reduced to experience. Like in the case of extreme empiricism, mediate judgments “never permit of rational justification, only of psychological explanation.” (p. 117).

The rational justification of mediate knowledge are psychological principles, which themselves require rational justification that cannot be obtained since these are psychological themselves. Hence Husserl writes: “The psychological premises of the theory are themselves mediate judgments of fact, and therefore lack all rational justification in the sense of the thesis to be established. In other words: the correctness of the theory presupposes the irrationality of its premisses, the correctness of the premisses the irrationality of the theory (or thesis).” (ibid). Since the principles of justification cannot themselves be rationally justified, they are irrational and yet somehow from these irrational principles we are to obtain correct theories!

One last thing to note concerning the appendix is this insight: psychologism and empiricism attack man’s rationality. They are a direct assault against the view that man is a rational being that can order himself around truths and laws of truth. The psychologistic interpretation of logic places those truths and laws of truths within man. Man becomes the measure of truth for his psychology dictates the laws of logic. As such, empiricism and psychologism are an inversion of the reality of logic and truth.

In a sense then, Husserl’s critique of psychologism opens the pathway towards personalism. Personalism asserts, defends, and promotes the rationality of man against ideologies and prejudices which renounce, assault or reject it. Psychologism is ultimately a rejection of man’s capacity to know truth and be a rational being, for how could a being be called rational if he is merely operating according to psychological laws? Animals behave in precisely this manner as non-logical beings. Psychologism is hence an implicit denial of the transcendence of man, i.e., man’s ability to know truth.

§27 Analogous objections against remaining psychological interpretations of our logical principle. Ambiguities as sources of delusion

There is a particular confusion now to which Husserl directs our attention. We have insight into logical laws when we have thoughts about logic. These laws possess a self-evidence that we experience through our encounter with logic. The psychologists confuse the thought-content, the logical laws themselves, for psychological phenomena; and hence they associate this self-evidence and insight of logical laws with psychological laws.    The absolute validity of logical laws is hence confused as an absolute validity of psychological laws and their self-evidency reinterpreted as something psychological.

Husserl replied to this scheme that if we can dismiss any justification for saying that two contradictory propositions cannot be both true as an insight of directly perceived truth, then the psychologistic interpretations of the law of noncontradiction must themselves be likewise dismissed; for what kind of absolute validity can the psychological view impose when the question of truth itself is dismissed? Whatever possibile validity the various psychological interpretations of the law of noncontradiction there are have become irrelevant if we cannot directly perceive truth itself (p. 118).

Husserl lists several psychologistic interpretations of the law of noncontradiction. His next step is to examine each of these interpretations. All of these interpretations possess in common the abuse of ambiguity and the task he assumes here is to expose these ambiguities.

The first interpretation is “that affirmation and negation exclude one another in our thought” (p. 118). The term ‘thought’ is used here ambiguously, since ‘thought’ applies to all intellectual activities. Some logicians, Husserl notes, use the term to apply it to correct judgment. This however raises the problem, correct judgment requires the exclusion of A and ~A (not A), but this is equivalent to a logical law and not a psychological law. As a logical law, this statement does not inform us about the possible situation of the coexistence of contradictory acts of judgment in one or many consciousnesses (p. 119). In other words, one person may assent to proposition A while a second person assents to proposition ~A. Each believes in either A or ~A, but not the proposition’s corresponding negation, i.e. the first person believes that A is correct and ~A is false, whereas the second person believes ~A is correct and A incorrect. The problem, however, is that on the psychologistic interpretation of logic it is impossible to determine who assents to the true proposition. The psychologistic interpretation of the law of noncontradiction given above is met in both persons without reference to the fundamental question concerning the state of affairs as to whether A or ~A is in fact the truth.

The second psychologistic formulation of the law of noncontradiction Husserl discusses states “that judgments recognized as contradictory cannot coexist in a single consciousness” (p. 118). Husserl makes two observations. First, this presupposes a conception of what is meant by a ‘normal’ consciousness. Logical laws do not presuppose such a concept. The concept of a ‘normal’ consciousness is irrelevant for a foundation of logic. The concept of ‘normal’ consciousness likewise presupposes this formulation of the law of noncontradiction, meaning that those who propose this interpretation of the logical law introduce a circularity. Secondly, once we remove this “metaphysical hypostatization” of the law, then the law of noncontradiction becomes nothing other than a logical law irrelevant to psychology, (p. 119).

The third and fourth psychologistic formulations interpret the law of noncontradiction as “that it is impossible for us to believe an explicit contradiction” and “that no one can take something to be and not to be at the same time” (p. 118). Both interpretations presuppose an extra condition, that it is impossible for a rational person to believe A and ~A. These interpretations of the law of noncontradiction are for those who desire to think and reason rationally, and as such do not apply to the irrational person or those who choose to act irrationally in a given instance. Husserl has two insights.

First, this highlights an important fact about logical laws, namely, that they do not possess psychological compulsion. The opposite can likewise be easily asserted. As Husserl wrote, “no psychological law drives the judging subject under the yoke of logical laws.” (p. 119).

Second, the psychologistic interpretation confuses the notion of  “cannot believe” as the non-coexistence of contradictory judgments with their incompatibility and non-realization of both statements being true. The content of the law of noncontradiction is this incompatibility and not the coexistence of judgments (cf. p. 119).

Husserl expanded upon this. This psychologistic interpretation of the law of noncontradiction presupposes the notion of a reasonable man. If one wants to be reasonable, they must think according to this logical law. The law of noncontradiction can hence be expanded into the formulation “No responsible, reasonable person can believe in contradictions”, but as Husserl noted, this is a trivial application of a general principle to a particular case (p. 120).  Someone who does not think in this manner is called unreasonable, but here there is no reference to a psychological law. The unreasonable person is judged accordingly by the laws of logic, not psychology.

These psychological interpretations of the law of noncontradiction possess a further ambiguity in the use of the word ‘impossibility’, for ‘impossibility’ can refer to the exclusion of the union of A and ~A, an exclusion by an objective law, or ‘impossibility’ can also refer to a subjective incapacity for such a union, i.e. a reasonable person cannot believe in contradictions, or, it is impossible for a consciousness to believe in contradictory propositions.

This impossibility raises another confusion. Sometimes one believes  proposition A as being true and possesses a feeling of certainty about its truth status. He or she may have several arguments and empirical evidence for its favor, and so feels a ‘felt resistance’ to the possibility that A is false and ~A is actually true. This subjective ‘felt resistance’ needs to be distinguished from the apodeictic inner evidence for a general law such as found in the law of noncontradiction. When one has insight into a logical law, for instance, he or she experiences a ‘felt resistance’ that this law must be this way and no other way, the logical law cannot be violated. This ‘felt resistance’ flows from the insight into the inner evidence of the laws of logic. Its content is ideal though the subject experiencing it is real. The ‘felt resistance’ of the individual who believed in a false proposition is properly speaking experiencing a psychological phenomena, bounded within space and time. It need not be only a ‘felt-resistance’ of erroneous propositions, for one can come to the conclusion that 2+2=4 after several experiences with manipulatives without obtaining the insight into its necessity. As Husserl stated: “One ought not to confuse assertoric inner evidence for the existence of a single experience, with the apodeictic inner evidence for the holding of a general law.” (p. 120).

Husserl now raises an interesting point. If one experiences only a psychological ‘felt-resistance’ of the truthfulness of the law of noncontradiction, that is to say, if one has accepted the validity for this law on empirical grounds alone, then this experienced ‘felt-resistance’ does not originate from the content of the law itself and the individual person does not possess its inner evidence. He or she has not yet grasped the necessity that A and ~A cannot both be true in the same respect nor experienced the ‘felt-resistance’ originating from insight.

The true situation concerning the law of noncontradiction is as follows: “we have apodeictic inner evidence, insight in the pointed sense, in regard to the not-both-being-true of contradictory propositions or the not-both-being-the-case of opposed states of affairs.” (p. 121). One observation we can make here is the equivalence between “apodeictic inner evidence” and “insight”. Husserl now applies this to the psychological problem. It is because we have this inner evidence of incompatibility that we can see how two contradictory judgments cannot coexist. Whether one believes so with assertoric or apodeictic inner evidence, it is this law as an ideal law which convicts us of the objective incompatibility.

There are two remaining sections in this chapter. I want to focus on one last theme from §29 and skip the remainder of the chapter. Husserl makes an important observation and used color to illustrate. When I see a colored object, let us say a red apple, the act of sight itself is an empirical act of observance, but the color itself remains. I can turn the apple around, adjust the lighting, and the apple’s redness will still be presented to me. It does not matter what kinds of changes are performed, the content of redness is still presented. In other words, the content of redness itself is not a merely empirical content, but is an ideal content. Red is something ideal, possessing an identity over against the many instantiations of redness itself. Husserl used color here as an example to illustrate this point: “meanings or concepts have identity in relation to the conceptions of which they are the ‘contents’.” (p. 128). Each concept is a supra-empirical unity falling under the laws of logic. Since this content is ideal, then the content of logical laws must likewise be universal, applicable everywhere.

If one wanted to object to this, Husserl would reply: “Our capacity to ideate universals in singulars, to have a ‘seeing’ grasp of a concept in an empirical presentation, and to be assured of the identity of our conceptual intentions in repeated presentation, is presupposed by the possibility of knowledge.” (ibid). If there were no ideal content of concepts which are particularized in individual conceptions, then the possibility of knowledge itself, according to Husserl, would be impossible. What Husserl wants to safeguard is the fact that the meaning-content, the concept, of logic itself must be ideal, for otherwise the laws of logic would lose their universal validity and become subject to the power responsible for that meaning-content. If, for example, logic’s content is something psychological, then man would possess power over the laws of logic.

The question I have for Husserl here is whether it is truly the case that “each single concept is in itself a supra-empirical unity” that is ideal (ibid), for this appears to treat the concept of unicorns equally as logic. Why should the concept of unicorns possess such an exalted epistemic position? If then a distinction needs to be made between these two kinds of concepts, then it raises the question as to what are the conditions that informs us that a concept is ideal or something like the unicorn. I refer the reader to two excellent studies: Dietrich von Hildebrand’s What is Philosophy, and Josef Seifert’s Back to the Things Themselves.

The Prolegomena

Prolegomena: Introduction

Prolegomena: Chapter 1

Prolegomena: Chapter 2

Prolegomena: Chapter 3

Prolegomena: Chapter 4

Prolegomena: Chapter 5

Prolegomena: Chapter 6

Prolegomena: Chapter 7

Prolegomena: Chapter 10

Prolegomena: Chapter 11

Looking Down Yosemite Valley, California by Albert Bierstadt

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