Grigory Mikhailovich Kogan was one of the most remarkable figures of his time. As a man of extraordinary scholarship, he spoke many languages, pianist, lecturer, critic and pedagogue, he was author of many books, on a variety of subjects, ranging from The Psychological Requisites for Pianistic Success, The Piano Texture, to Ferrucio Busoni, Couperin, the important monography The Pianist's Work, etc. Read two Chapters from the first English edition of "Busoni" by Kogan. More chapters of this book you can read on interesting and informative web site of Svetlana Belsky (Translator of this book) by the following link.
He also edited a number of piano pieces and music books, wrote articles in newspapers, magazines and encyclopedias, wrote concert and book reviews, school curriculums, etc.
Grigory Kogan defended his doctoral dissertation at the age of 19 and soon became professor of Kiev Conservatory. He was also an art historian, scholar and polemicist, and was very influential to a whole generation of Soviet pianists through his lectures, books, reviews, articles and concerts.
Kogan came to Kiev in 1911 at the age of 10 and lived there for 15 years, until 1926.  At that time Kiev was already an important center of music and culture.
Before the Revolution, the Kiev Conservatory functioned differently than it does now. A Society for Economic Help to Students was created, and it organized many concerts. The income went to students in need. Thanks to that society, people from Kiev were able to hear many remarkable artists.
As a pianist, Grigory Kogan had a huge repertoire and enjoyed a very intensive concert schedule. Apart from solo recitals, he also played piano duets with Grigory Ginzburg and Heinrich Neuhaus. Later, as professor of Moscow Conservatory, he created a course called History and Theory of Pianism, the first of its type.
The success of his lectures was overwhelming. Not only pianists, but students and professors of different musical fields attended them, and Kogan was constantly invited to lecture around the country.
It was highly interesting and educational to hear him talk about remarkable musicians, conductors, pianists that he had heard and met in his life. He also had a tremendous sense of humor.
Grigory Kogan was an outstanding teacher. When listening to someone play, he would immediately recognize and figure out the exact problem that made something not work, and immediately gave an exhaustive solution to the problem.
In the late 40's, during the well-known campaign against cosmopolitism in the Soviet Union, cruel and false accusations were made against many outstanding figures. The intellectuals were the prime victims of this campaign. The most prominent Soviet composers were absurdly accused of diverging from the mainstream of Russian tradition. As a result of this campaign, Grigory Kogan lost his position at the Moscow Conservatory. His constant references to foreign publications, authors and thinkers, his own books and articles about foreign masters, such as Busoni, were "sufficient grounds" for accusing and dismissing him.
Soon after this, however, the well-known composer and director of the Kazan Conservatory, Nazib Zhiganov, offered him a teaching position there. Zhiganov practically saved his professional life and dignity at the time of "cosmopolitism".
Kogan quickly became a central figure of Kazan's intellectual life. Among his students there was Sofia Gubaidulina, who would become one of the century's leading avant-garde composers, whose outstanding talent Kogan determined very early.
In recent interview Gubaidulina said: "I completed my piano studies at Kazan Conservatory at the studio of Grigory Kogan, who was a professor there at the time. The supreme level of professionalism and the impeccable sense of taste in music permeated every lesson I had with him. Although Kogan did not teach composition, the scope of his perspective in art, and his attitude toward the musical material have greatly influenced my decision to become a composer."
Years later, upon returning to Moscow, he concentrated intensively on writing and performing. At this time, his main books were being published as well as numerous articles and concert reviews. However, he was never allowed to go abroad, which is the reason why he is not yet well known in the West.
I have always maintained a strong musical and human rapport with Kogan. Even years later, when I moved to the USA, we maintained a very active correspondence.
Kogan's book "Busoni as pianist" is now available in English (translated by Svetlana Belsky) on amazon.com.
 During the last few years before the Revolution, it was possible to hear in Kiev composers like Rachmaninov, Scriabin, Medtner, Gretchaninov, young Prokofiev, conductors Kuper, Kouts, Malko, Koussevitzky, Fried, pianists Hoffman, Godovsky, Yesipova, Slivinsky, Borovsky, Beklemishev, Neuhaus, young Arthur Rubinstein, harpsichordist Wanda Landowska, violinists E. Ysaye, Auer, Kreisler, Milstein, Erdenko, young Heifetz, cellists Casals, Kosolupov, Press, singers Nina Koshitz, Sbrueva, Lodi. At the Opera sang Chaliapin, Moszhukin, Baklanov, Battistini, De Lucca, Sobinov, Smirnoff, and Maria Galvani. In Drama Theater Yureneva, Plievitskaya, Radin, Varlamov, Davidov, Orlenev, M. Chekov. Dancers Gelzer, Mortkin, Previashenskaya. The MXAT with Stanislavsky, Kachalov, Moskvin, Leonidov, Lilina, Knipper-Chekhova, and Theatre Vajtangova, with their unforgettable TURANDOT. Lectures and poetry readings were given by Balmont, Mayakovskiy, Ivanov. They all came to Kiev. In 1913 was opened Kiev Conservatory. Before that, there were only two conservatories in Russia, St. Petersburg and Moscow. At the end of that period were opened three more: Kiev, Odessa, and Saratov. At Kiev, since the beginning, there was a very strong group of outstanding pedagogues. Piano professors included Pukhalsky, Dombrovsky, Beklemishev, Blumenfeld, and Neuhaus. Violin professors were Erdenko, Kokhansky, cello teachers were Kosolupov, Press, voice teachers, Gandolfi, composition teacher Glier, Yavorsky, Liatoshinsky.Needless to say, in such an atmosphere many musicians later became outstanding performers, composers and musicologists; pianists Horowitz, Uninsky, Brailowsky, Tamarkina, Kaplan, Lufer. Composers Revutsky, Liatoshinsky. Pedagogues Artobolevskaya, Liebermann, Yankelevich. Musicologists Alshwang, Belza, Pekelis, Zukerman, Levik, Grienberg-Sokolsky. Singers, Norzov, Zoya Gaiday, and many others.