"A classification of all forms of violating the relevance principle as systematic as that of plants and animals could be very helpful": this is what was stated in the previous chapter. There it was pointed out, too, that traditional language has already bestowed a special name on a limited number of exclusivisms. Racism, sexism and nationalism are three stereotyped examples. In one respect we find ourselves in the primeval position of the science of biology before it started to methodically classify plants and animals. Every vernacular language already used to have names for a certain number of kinds of living being, but other kinds of living being had no names at all. And the vernacular name was not necessarily the name of a species, that is, a specific name; quite often it was a superspecific name denoting an entire genus, or a subspecific name denoting a subspecies, race or variety of the species. Similarly, a vernacular or traditional language may at the moment have a word for sexism and racism, without having a word for exclusivism on the basis of age or denominational doctrine adhered to. Or, such a language may have a word for anthropocentrism (a name on the specific level) and for infrafactorial racialism (a name on the subspecific level), without having a word for abnegational anthropic exclusivism, interfactorial racialism and other exclusivisms on the specific, subspecific and other levels.

The analogy between the classification of plants or animals and the classification of the myriad manifestations of exclusivism in the world is only valid insofar as it is descriptive. A classification is descriptive if concerned with taxons recognized as separate entities from the beginning on, particularly when they do already have a name in the vernacular or traditional language. Such a classification has to search for the criterions which divide and unite the taxons known. (Alternatively, this aspect has been called "the accidental aspect".) However, when novel taxons emerge, or are made to emerge, due to the process of categorization itself, the classification is speculative (or 'functional' as it has also been called). That it is 'speculative' does not mean that the taxon or taxons do not exist in reality; if so, they merely have not been discovered or recognized yet. It is precisely because a systematic arrangement suggests their existence that the taxonomist or other person starts looking for them. (Thus, physicists have discovered new particles on the basis of a partially speculative classification system.)

From our point of view it is important that the norm of inclusivity rejects both exclusivisms which did and do exist and exclusivisms which will exist, or which could be made to exist. This is because our world-view is, unlike the scientific one, primarily normative. For us it is particularly the speculative aspect of surveying 'the irrelevant' which, if systematic, makes it possible that the recognition of direct and indirect manifestations of exclusivist beliefs, thoughts, feelings, tendencies and actions is no longer dependent upon everyday or traditional language. The absence of a suitable terminology for many manifestations of exclusivism in the conventional vocabulary of this and other tongues need, then, no longer be prejudicial to our moral outlook. The reason is that the limited number for which there is a simple word in that conventional vocabulary (and for which a descriptive, accidental classification would suffice) must not be considered as approximating, let alone representing, the total range of exclusivism in any way, even not in purely moral contexts. Yet, if discrimination or exclusivism is wrong, every form of discrimination or exclusivism is wrong, regardless of what or whom is disparaged, and regardless of the gravity of the exclusivist attitude or practise from other angles. The more orderly a classification of the violations of the norm of inclusivity, the greater the number of actual or possible manifestations which will be brought to light, and the better this classification will clarify the scope of the inclusive norm itself. (This will require the introduction of quite a few technical expressions. If the number of these new expressions seems large, or too large, the reader or listener should not only compare it with the technical terms and scientific names biologists were forced to introduce but also with something like pneumonoultramicroscopicsilicovolcanoconiosis in medical jargon. In any event the terminology of the present classification system of exclusivisms will be much simpler than the tables of exclusivist forms of address covering so many superfluous pages in traditional dictionaries and diaries.)

No systematic taxonomy will include hybrids in its 'primary' system, because hybrids are the offspring of two members (such as animals or plants) of different subspecies, species or genera. To determine these subspecies, species or genera a scientist or other person must already have a system in which these nonhybridous taxons are classified at 'er disposal. The 'primary' system is therefore already presupposed before anyone can speak of "hybrids". Similarly, the classification of exclusivisms starts with that of singular exclusivisms, that is, exclusivisms of which the object of exclusion or exclusivity is determined by one single factor. Plural exclusivisms, on the other hand, are constituted of different kinds of exclusion or exclusivity. As the x-raying of singular exclusivisms should be sufficient to indirectly reveal and locate plural exclusivisms as well, we shall not endeavor to systematically categorize the latter in this Model.

Given that exclusivism amounts to violating the norm of inclusivity, not violating this norm (while being able to do so or to want this) in the same respect and 'in the same way' is a particular form of inclusivity. Hence, we shall say that 'every manifestation of exclusivism is antithetical to a certain facet of inclusivity'. By arranging the facets of inclusivity so as to run parallel to the manifestations of exclusivism, the survey of exclusivisms can indirectly also serve as a survey of the facets of inclusivity. We could not do the reverse, however, for several singular manifestations of exclusivism (male and female exclusivism, for instance) may correspond to only one facet of inclusivity (gender-neutral inclusivity), whereas a singular manifestation of exclusivism will never correspond to two or more facets of inclusivity.

The word irrelevantism may be employed as a synonym of exclusivism, but an obvious difference is that exclusivism stresses what is irrelevant according to the interpretation laid down in the norm of inclusivity. It could also be said that the usage of exclusivism, and of inclusivism too, is denominational, that is, ideological, while the usage of irrelevantism and relevantism is, for example, more philosophical. In a philosophical context the equal, unless approach might thus be called "the position of relevantistic egalitarianism" rather than "inclusivistic egalitarianism". In practise tho, it is the interpretation of principles and people's attitudes which count, and therefore the antithesis between an interpreted exclusivism and its manifestations on the one hand and an interpreted inclusivity and its facets on the other.

For the purpose of the classification system to be presented in this chapter we shall confine ourselves to nonrelevant distinctions drawn by human agents or decision-makers. Moreover, we shall use the phrase human being in the conveniently ambiguous sense of either human body or human person (that is, person who has a human body). But even the task of x-raying all attitudes and practises in which nonrelevant distinctions are or can be made by human beings may seem impossible. The impossibility of this task, however, need not deter us from classifying those human, contemporary and historical, singular exclusivisms which are already named in traditional language, those human singular exclusivisms which are related to them and should be listed, if the former ones are, and a number of other singular exclusivisms, particularly in the sphere of human or happiness-catenal relations. It is theoretically possible to x all these exclusivisms or irrelevantisms by using a system of dichotomous subdivisions in such a way that every lower-level exclusivism which does not belong to the one subdivision belongs to the other, whether it is mentioned itself or not. When representing this system of dichotomous subdivisions in a diagram the resulting picture roughly resembles that of a tree (or of a tree turned upside down). Starting from (universal) exclusivism each branch then represents a lower-level manifestation of exclusivism.

An easy way to keep track of the ramifications of human exclusivism is by using a binary-decimal system of numbering. Such a system consists of the decimal equivalents of the numbers obtained by reading the code of an entirely dichotomous classification as one binary number (instead of as a set of binary numbers each representing one classificatory level). (For example, the decimal number 9 corresponds to a binary number 1001 which stands for 1.0.0.1.) This system requires that every nomenclatural level of a trichotomous, tetratomic, pentatomic or polytomic subdivision be replaced first by two or more levels of dichotomous subdivisions. But if the nondichotomous subdivision is not logically exhaustive, this only enhances the reliability of the classification system, because the dichotomous taxonomy, if properly applied, has a built-in safeguard against neglecting or arbitrarily leaving out any lower-level exclusivism. When, in this chapter, a name is succeeded by a letter and one or more numbers in parentheses, X stands for manifestation of eXclusivism, N for facet of iNclusivity or Neutral-inclusivity, while the number is part of a binary-decimal enumeration system. Furthermore, it should be noted that we will use exism as a convenient abbreviation of exclusivism (and re as short for with respect/regard to). An alternative abbreviation of exclusivism is x-ism (or Xism when capitalized). Exism and x-ism will later be used too as abbreviations of extremism in the catenical sense.