12 JUNE 1937 * 3 JUNE 2010TODAY, 12 JUNE 2010, Vladimir Igorevich Arnold, or VIA, as we used to abbreviate his name between ourselves in writing, should have turned seventy-three. Today, as many times on this day in the past years, I should have been writing a short informal Happy Birthday email that never was acknowledged - VIA was not known for wasting time on polite conversations - yet I knew he would have read it. If I were in Paris, I would call and drop by - as all of his students would do.Instead, today we are waiting for our teacher to be laid to rest: the funeral in Moscow is scheduled for 15 June. VIA died of foudroyant pancreatitis on 3 June 2010.The mere thought of Arnold's being ill contradicts his personality as we remember him. All his life VIA projected strength, confidence, perfection, beauty, elegance. He was all motion, all burst. I remember him teaching the second-year class on ordinary differential equations in the huge hall 16-24 in the Moscow University main building. At the beginning of each class he rushed in, with his trademark briefcase with the last sound bite of the bell, starting the first phrase of the lecture while still three to four meters from the blackboard. In a fraction of a second his briefcase was thrown on the table, a piece of chalk appeared in his hand, and, when the first phrase was completed, we already saw a carefully drawn picture on the blackboard and a few formulas written in his calligraphic handwriting near it. His lectures were impossible to write down, as impossible as it is to record by a cell phone a superb performance of your favorite music. Besides, it was very difficult to record the insight. As Arnold speaks, draws, writes, you suddenly see how different things are getting connected and the whole picture transpires through the initial fog. Fortunately, at that time his famous textbooks were already published; in those books he succeeded in doing the impossible by recording these revelations.Later I started attending the famous Arnold's Seminar (with the capital S). It will certainly be described by many people who were closer to VIA and who have sharper pens, yet this phenomenon was unique, so that no detail should fall into oblivion. The Seminar was scheduled so that people could attend it after the standard office hours, as many (probably the majority) of the participants were not officially affiliated with Moscow University. Arnold rushed into the room and took his permanent seat in the middle of the front row next to the blackboard. The Seminar did not begin until VIA got from the briefcase a bunch of recent preprints and reprints and handed them out to the elder participants of the Seminar: [to Vassiliev]! The author claims that he proved so-and-so, but I could not find any appearance of the contact structure in his computations. This simply cannot happen, we both know that it should be somewhere there! (And in a couple of weeks Vitya would indeed return the manuscript to VIA with margins peppered with remarks explaining where the missing structure was concealed and showing how its explicit use may simplify the proof.) This home assignment could take quite a bit of time, yet at some moment Arnold opened his school-like copybook, entered the name and the title of the talk, and the Seminar began.The choice of speakers and the titles, apparently, reflected the current interests of VIA; for me (at that time a fourth-year undergraduate student) neither was telling, yet this was largely irrelevant since each Seminar was a one-man performance. A typical scenario was as follows. For the first fifteen to twenty minutes the speaker talked practically uninterrupted - no more than once in one or two minutes, when VIA asked questions seemingly technical or even bordering on chicanery. Gradually the exposition turned into an agitated conversation between the speaker and Arnold; this ping-pong could last long enough for the rest of the audience to get completely lost. …