[Sorry, couldn’t post these past few days as the internet connection at our new apartment here in Munich wasn’t functioning.  Welcome to super-efficient Germany!  But it’s fixed now.]

Carnap was involved in the international language movement all his life. From the age of 14 — as he himself points out, before he had encountered any logical languages — he was an Esperanto enthusiast and after 1918 went to a number of international Esperanto conferences. We know from McElvenny that — without putting Esperanto aside — he became involved in Ogden’s project of Basic English. And later, in North America, he became an active participant in the International Auxiliary Language Association (I.A.L.A.) — copious notes and comments exist in his papers about the various proposals considered by the association. But the only thing he ever published on the subject, apart from the highly abbreviated remarks in his autobiography (the original passage on this subject is roughly three times as long), was a brief 1944 letter to the editor of a periodical called Books Abroad in which he comments on an article published there by Pierre Delattre. This article, as Carnap says, “points out some serious disadvantages of Basic English: the irregular spelling, the difficulties of pronunciation, the use of numerous figurative and idiomatic phrases, the irregularity of the tonic accent.”  Those who consider Carnap to have been an inflexible rationalist prone to rigid dichotomies (e.g. Thomas Mormann in his otherwise mostly superb little introductory paperback on Carnap, p. 36) will take satisfaction in his response to Delattre’s criticisms: “I think he is right in all these points.”

But the point of Carnap’s letter is precisely to undermine Delattre’s entire conception — “And yet,” Carnap continues, after agreeing with the French scholar’s predictable critique of the illogicality of English, “he does not even touch the decisive point of the problem raised by Basic English.” Which is that since the need for an international auxiliary language is growing, and “therefore we shall have it,” we have no idea whether Basic English or some alternative is going to prove most useful in the end. Logic and consistency are virtues in an auxiliary language, certainly, but they are not the only virtues, and perhaps not the most important ones. And if not, then Basic English “will be used . . . in spite of all its disadvantages. Man never has perfect tools. He uses the relatively best available” – i.e. the best considering all the trade-offs between various possible virtues.

This is not, of course, how Carnap is usually portrayed. We hear, rather, of his confinement to the “icy slopes of logic,” in contrast to Neurath’s proto-Mark-Wilson-like appreciation for the messiness of actual human cognitive and engineering projects. But here, in this letter to the editor, he tells us straight out that our actual tools are never as perfect as logic might like them to be, and that to decide which ones to use, we have to take the messy reality into account. I am inclined, like Thomas Uebel, to see the influence of Neurath here. (I actually think this influence is already clearly visible in the self-irony of Carnap’s classification of himself in 1929 as working on the “icy slopes of logic.”)

There are two ways, Carnap continues, of going about the construction of an international auxiliary language:

. . .we may carve out a simplified part from a natural language, like Basic English, or we may create an artificial language, like Esperanto. The latter way has, as Dr. Delattre mentions, the advantage of a much greater simplicity and regularity. On the other hand, Basic English or Basic Chinese has the great practical advantage of being immediately understandable to millions of people.

Carnap has no doubt, he says, that in a few decades “there will be an international language of simple structure in general use as the second language of all people on earth who can read and write.” But we have no way of knowing which practical advantages will turn out to dominate in the choice of language: “. . . nobody knows today whether it will be a basic language or an artificial one. Therefore, both ways must be tried out.”

This is obviously an application of the principle of tolerance. Elsewhere, Carnap makes this explicit. In the original draft of the autobiography, after discussing a number of the auxiliary language projects of the twentieth century, he mentions that “heated sectarian debates are going on” among their adherents.  His own position regarding these disputes?  “As in the field of logical languages, I pleaded for the principle of tolerance.” (UCLA Ms. Coll. 1029, Box 2, CM3, M-A5, p. N26[a]) He himself clearly did not limit the scope of the principle to the philosophy of mathematics or to ontological conceptions. As we see from the present example, the “external” question concerning the “correct” international language need not even involve a metaphysical view about what “really” exists; to qualify as external it need merely merely make a claim that exceeds our current capacity to bring convincing evidence to bear on the question.  So the class of external questions is far larger than the strictly metaphysical ones; it includes all questions we are not in a position to decide with the tools available within any clearly specifiable, agreed framework.  There will be more to say about this.

It could be pointed out, of course, that Carnap’s tolerance in this case didn’t actually go far enough, or at least that the scope of envisaged alternatives was too narrow.  He claims in this letter that if a Basic language is chosen, then English is well-placed, and

But English has been chosen as the raw material, and Ogden’s Basic English has become a mere historical curiosity.  The Globish we seem to be stuck with is a loose collection of creoles and dialects with no real standard reference forms other than the standarized natural language dialects (UK English, American) they are based on.  It looks rather utopian, in retrospect, to have imagined a consensus on an artificial standard.  Again, there is a lot more to say here.

Carnap ends his letter with a brief history of artificial language projects (of both kinds) since Esperanto, emphasizing that progress has been made and systematic research has led to better forms.  Another important component of Carnapian rationality is expressed here — the emphasis on constructive experimentation in place of recondite Erörterungen: let’s not just sit around and talk about this stuff in the abstract, let’s roll up our sleeves and get building, and see what happens.  This is the same message Carnap conveys in his reply to Ernest Nagel in the Schilpp volume (on inductive logic), and the attitude that is most profoundly at odds with philosophy as now mostly practiced.  “A good deal of further work must be done in this field,” Carnap concludes.  “Criticism of existing projects is not enough — constructive proposals for improvement are required.”