Professor Arguelles writes at some length about this on his website.
QUOTE:
“…I applied for professorships at a number of Korean universities and so obtained a faculty position at Handong University on the eastern coast of the country…(…)…the campus was on an isolated hill amidst pine and bamboo forests and rice fields with a view of the Pacific Ocean from my back porch…”
"…It was in the period 1996-2001, when I was between the ages of 32 and 37, that I finally truly achieved my dream of being able to study in a focused and protracted fashion to turn myself into a polyglot by learning as many languages as I could, as well as I could. Initially, of course, I focused on Korean and, after I got grounded, on Classical Chinese and Japanese in a comparative context. However, I also ranged very widely through the whole world of languages. I had a decent salary and no debts or real expenses, so I was able to order grammars, dictionaries, and tapes for the study of absolutely everything that I could find and thus I collected a personal language resource center that now contains materials for the study over 150 different languages. Although I could not get to all of these, when I received them I went through them with the goal of learning at least something about at least one language of each representative type or from each language family. As a product of Western civilization, I cannot help but draw a fundamental line between the way I can relate to European Indo-European languages on the one hand and all other “Exotica” on the other. In the first case, in this period I not only strove to keep up all the languages I had already studied, but I tried to get an overview of all the Germanic and Romance dialects that I had not yet examined, and I also began to explore the Celtic and Slavic families as well as Modern Greek. In the second case, I began the study of many languages in which I never got very far (Euskara, Finnish, Shona, Zulu, Ancient Egyptian, Quechua, and Malay-Indonesian spring to mind most immediately now), as well as others that I covered quite systematically before abandoning them for years (Swahili and Turkish), others that I have never abandoned even if I have not always been able to give them regular care (Hindi-Urdu), and yet others that have been my near daily companions ever since (Arabic and Persian).
In order to do this, I led a monastic existence, obsessively studying languages all day, every day. Of my 18 waking hours, I often managed to devote 16 to linguistic pursuits throughout this period. How was I able to sustain the momentum to study with such intensity? To begin with, the nature of my job greatly facilitated this degree of immersion. Teaching foreign languages, at least for the first few years, was a continuous language learning experience in itself, and the essence of my research activities also involved the in-depth study of Korean, so I could count most of my working time as study time as well. Furthermore, I was still a bachelor, living in an isolated rural environment, so I had no external demands upon my time. Because of this, I was swiftly able to discover and adhere to what I regard as my natural sleep cycle, which is to go down with the sun and wake up six hours later. The exact time varies with the seasons, but given that this is basically from 8:00 PM to 2:00 AM, this was not something I was ever able to do as a normal socially active adult. However, in my relative isolation, I found that when I kept a strictly regular schedule based around these hours, I was able to remain completely focused and alert throughout my entire waking day.
Thus, in this five-year period from 1996-2001, I was able to explore scores of languages and to build a solid foundation in a fair portion of them, but thereafter I brought this period of my life to a close for several reasons. For one thing, throughout this period I had been focusing on learning new languages to the exclusion of reading books in or otherwise using and enjoying languages I had already learned well, and after a steady diet of textbooks for five years, I was hungry for literary works and philosophical treatises again. More importantly, though, I had come to realize that I was essentially “full,” or even past my holding capacity. That is, even with the most rigorously planned and systematically maintained scheduling of the shortest bursts of study times, there was simply no way I could fit any more languages into my daily regimen or even balance them by juggling alternately recurring cyclical schedules. Most importantly of all, however, I was coming to understand the nature of language learning curves better and better:
The essence of what I had been doing throughout this period was textbook study - working through multiple manuals and getting very adept at the process. However, while foreign language learning (i.e., getting a foundation in a new language) gets easier and easier with experience and skill, making progress in foreign languages still inevitably and necessarily requires greater and greater investments of time. There are, of course, no clear cut points in language knowledge, but still if it takes one unit of time to go from 0 knowledge to a certain point A, then it takes two units of time to develop from point A to point B, and four units of time to develop from point B to point C, and so on geometrically until an ultimate point Z. In other words, while getting a solid grounding in a language is relatively easy, developing more advanced knowledge quite simply takes much longer. Now, while there is nothing unsatisfying about working through a language manual at a pace of 15 minutes a day, each and every single day, when it comes to more advanced “studying,” i.e., when you want to read, be immersed in, and follow the development of narratives or of expositions of chains of thought, it is quite unsatisfying to be limited to such short spans of time. Such activity calls for engagement on the scale of at least an hour at a stretch, and indeed, when reading an exciting and powerfully written story or an important and meaningful argument, it is painful to have to parcel one’s time at all.
I had been coming to this realization anyway, but it truly hit me in February 2001 after I returned from a month’s home-stay with a Russian family in Saint Petersburg, where I had one-on-one conversational lessons with a private tutor for six hours a day. I went there at that point because I felt that I had taught myself as much as a I could on my own and that I was ready for this intensive immersion so as to activate my knowledge of the language and bring it to life. By the end of the stay, I had attained a high level of conversational ability, both about everyday life and spanning the intellectual humanities. However, when I tried to sit down and read the works of Turgenev or Dostoyevsky that I purchased there, I found that I was still way over my head, the range of literary vocabulary being so much wider than that of spoken language.
Thus, in order to continue working towards this goal with Russian required a break with my established routine. So, too, did allowing myself to revel once again in French, German, Spanish, Latin, and Old Norse, as well as for the first time in other Romance and Teutonic tongues. In addition, my Persian, Arabic, Hindi, and Greek were all about where my Russian was before my trip, and at any rate I was well beyond any textbooks with them and into “advanced” annotated readers. How could I possibly find an hour a day for each of them and at the same time continue to parcel out 15 minute slots to Japanese, Chinese, Swahili, Turkish, Czech, Welsh, etc., as well as to continue to factor in the likes of Tamil, Tibetan, or Thai? I clearly and simply could not. So, at this point, I resolved not to add any more new languages, and indeed I also slowly began the painful process of aborting and abandoning many others. Until this point, I had been driven by curiosity to learn as much as I could about as many as I could and it seemed to me that I had never studied enough languages; after this point, I was driven to master the reading of a more manageable number, and it seemed to me that I had studied all too absurdly many…"
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