1 Irrationalism is not so much a distrust of one's own reasoning or of reason in general, but a distrust of the reason of others, especially public reason (or „the masses“).
1.01 An Irrationalist therefore may or may not perceive himself as „rational“. He may or may not play the rational discourse. (He may doubt the ability of others to play this discourse though.)
1.011 An Irrationalist may even turn rationality into an absolute. (An example would be Ayn Rand and her followers.)
1.1 An Irrationalist may either deny the ability of the public to use reason to civilize itself (therefore assuming that only privileged individuals can or do use their reason this way), or he may posit a realm of transcendent insight open only to himself or a few „chosen ones“ and therefore inaccessible to public reasoning.
1.2 Although Irrationalism may be elitist, it's not so much a form of elitism (in opposition to egalitarism) as of epistemic particularism (in opposition to universalism).
1.201 Universalist forms of elitism do exist.
1.21 What an Irrationalist claims to have is a privileged particular position of insight. (But not all claims of epistemologically privileged positions are Irrationalist, as long as they are, at least in principle, universally accessible and, therefore, open to criticism and public discourse.)
1.211 What Irrationalism tries to shut out, destroy or openly deny, is a critical and universalist publicity.
1.212 Irrationalist epistemology is, therefore, profoundly anti-democratic.
1.2121 (If an Irrationalist perceives or defines himself as a democrat, he will most probably have a rather limited concept and understanding of democracy, either binding it to certain limiting forms (of politics, economy, or public life), political institutions or positions, or to so-called „democratic elites“, or all of this.)

2 Irrationalism is not to be confused with irrationality, irrational behaviour, or the „irrational“ aspects of human life (emotions, religion, art, intuition, spirituality, magick, and so on), nor is it a form of madness or insanity. Rather, Irrationalism is a certain form of positioning oneself towards questions of epistemology and politics, which privileges a particular (not universally accessible) position of insight over public discourse, openness, and civility.
2.01 Consider Science Fiction series. In X-Files, it is the bad guys that desperately try to hide things from public view, while the good guys want to find the truth and reveal it to the public, and are driven by the critical discourse between them. In Stargate or Men in Black, the good guys already know the truth and deliberately hide it from the public, because in their eyes, the „ordinary“ people a priori cannot be trusted to deal with „this kind of information“.
2.011 It follows that, although X-Files does contain un-scientific content, it does not promote Irrationalism, while Stargate does. Consequently, „irrationalist“ and „unscientific“ are not synonymous concepts (although they can go together). The (pseudo-platonic) wish for an elitist society governed by an elite of scientists and experts who shut out the rest of society from discourse is irrationalist.
2.1 Irrationalism could be seen as a certain form of mediation between reason and madness.
2.101 However, although it's tempting to do so, Irrationalism cannot just be thought in terms of „privilegeing or over-emphasizing one side over the other“, therefore opting for a „Yin-Yang“ kind of pre-stabilized balance or harmony of both. (Or better, since such a harmony can only be defined as a universally unaccessible particularity, such a definition of Irrationalism would be irrationalist in and of itself.)
2.11 Although madness and reason are not synonymous concepts, they are neither completely distinct nor completely seperated, but interconnected. Every form of reason does carry a seed of madness (or contingency) in it that at the same time stabilizes and threatens to destabilize it. On the other hand, there is no madness that could not (at least in principle) be rationalized (or symbolized) in one way or the other.
2.1101 (One could say that „the destruction of reason“ is a result of the Irrationalist denial of the contingent core of reason itself.)
2.1102 (Madness and reasoning can be seen as two different ways of speaking (or „using language“), although possibly not the only ones.)
2.111 It is exactly because of this intrinsic, unbreakable relation that the rationalist does trust public discourse and reasoning and calls for it.
2.2 Do we say that Irrationalism is the exclusion of some beliefs or insights from public discourse, while Rationalism is (at least in principle) ready to openly discuss everything? Not quite. Irrationalists and Rationalists both do have beliefs that they do not subject to discussion. The difference is that while Irrationalism roots its beliefs in the claim of a particular, epistemologically privileged position of insight (thereby denying that public discourse can even understand them), Rationalism affirms the contingency of one's choice for or against them, as well as the ability of the public to (at least in principle) investigate and understand them. 2.201 In a way, Rationalism is closer to madness than Irrationalism. (It is also closer to reason.)
2.21 Irrationalism roots its beliefs and insights in a particular position of gnosis or enlightenment, while Rationalism roots them in everyday life, habits, tradition, social practice, production, work, practice in general, act, and (individual or collective) choice. (Wittgenstein: „Our reasoning ends, and then we act.“)
2.2101 (Therefore, Irrationalists not so much exclude their beliefs from public discourse, but public discourse from their beliefs.)
2.211 Since Rationalism is rooted in the complexity of everyday life, the contingency of choice and act which are always born from confusion (incomplete knowledge), and in the discord that motors public discourse, Rationalists may be called Discordians. And since Irrationalism is rooted in the claim of a particular position of gnosis and enlightenment, supposedly positioned outside everyday life, choice, contingency, and revision by new information or critical investigation (and therefore outside public discourse), Irrationalists may be called Illuminates. (Another appropriate pair of terms would be „materialist“ and „idealist“.)

3 Is this text just another form of Popper-ian (or Rorty-ian) liberal pluralism? Not quite. The core question here is Rationalism's own relation to Irrationalism.
3.1 Rationalism, with it's call for public discourse and civility, necessarily reaches the point where, in order to stabilize itself as a theoretical position, has to opt for the limitation of public discourse in order to subtract it from Irrationalism. Karl Popper did not further problematize this, but on the contrary fully and openly affirmed it, thereby (probably) un-intentionally camouflaging its constitutive ambiguity.
3.11 A consequently irrationalist public (for example, a public subscribing to Catholicism, believing that only the priests of the Catholic Church have a privileged access to the Truth) would renounce the whole language of this text, and therefore be excluded from the rationalists' understanding (or, which is the same, theoretical and practical use) of it. Therefore (since we partly defined Rationalism and Irrationalism in terms of their relation to public discourse) when public discourse itself becomes irrationalist, an optical shift occurs in which Rationalism and Irrationalism seem to „change places“ or become indistinguishable.

4 The root of our problem seems to lie in the deeply ambiguous, antinomian and at the same time un-avoidable link between epistemology and politics.

(K) Sankt Angrémonn der Hastige, KSC, Direktor AISB.
Written some time between 2007 and 2009.
Revised January 2016.