买了一幅Mandelbrot集局部特写挂在墙上，算是自己收藏的第一幅美术品。住在Dell House的时候在墙上挂过两幅励志海报，不过后来觉得也没起到啥励志的作用，又不好看，搬家以后就不挂了。还是装在框里面的画比较有感觉。 最初接触到Mandelbrot集是在初中的时候看《上帝与新物理学》（God and the New Physics）这本书上，讲到了Julia集，Mandelbrot集和Belousov-Zhabotinsky化学振荡等非线性现象，后来又买了两本专门讲分形的中文科普书，其中有一门科学出版社的图文并茂非常引人入胜。Mandelbrot集和Julia集的数学定义非常简单，就是复数乘法加法的迭代，何以能产生如此惊人复杂的图案，至今让我百思不得其解。我一直都梦想能够挂一幅Mandelbrot的画在书房墙壁上，今天算是梦想成真。Mandelbrot集不仅复杂而且极端美丽，其美丽程度远远胜过任何人类可以想出的几何图案。记得曾经装了个linux上的xaos，连续几个小时zoom来zoom去欣赏得乐此不疲。我想，如果哪位艺术家有权在Mandelbrot集上署名的话，那大概只有大自然或者上帝。

数学的美大概有两种，一种是隐性的美，体现在自洽、简洁和高度抽象的概念和逻辑体系上；另一种是显性的美，分形大概就是这种美的代表。这两种美，只有在纯数学里面才看得到。至少对于我来说，应用数学很难给人美的感觉。本来应用数学追求的就是实用，境界不一样。神经科学看多了，难免对数学产生失望。这个领域里大量的应用数学，看多了让人身心疲惫，一点也不像看纯数学时那种如沐春风的感觉。不是因为公式和概念的复杂，而是因为其大量牵强附会的假设、少的可怜的推论。尤其是一些故弄玄虚的理论神经科学论文，似乎是故意地把读者搞得一头雾水，看了以后简直令人恼火和恶心！（也许是我还没有领悟那些paper的精髓，所以在这里乱发牢骚。）脑是如此复杂，大概不是按照人类的数学设计的，所以企图用数学来解释脑，最终只能陷入平庸的努力和无助的叹息。但是看看Mandelbrot集，如果对此一无所知的话，又有谁会猜到它是源于一个如此简单的数学公式呢？所以从这个意义上，Mandelbrot集给了我一丝丝希望和安慰。

My sincere thanks to you all who showed up at the concert tonight! It was you that made our performance meaningful. And partly because of that, I feel that it was the best one among the three JHU wind ensemble concerts I have played since I came to Hopkins. In fact, that performance was quite good, at least for us "engineers" (and scientists and humanity scholars, of course). It's the first time I played the JHU Ode without a wrong note (shame on me :p). The opening of Alfred Reed's Festival Preluded was a little weak, but fortunately ended up well. Percy Grainger's Lincolnshire Posy was fun. Our painstaking effort finally paid off a bit. Illiad was okay although the cymbal guy was habitually late by half a beat. I definitely could hear some Wagner in Elsa's Precession. And as many of you commented to me, the jazzy Music from the Incredibles was a hit.

My passion in playing in bands has been fading since I left THUMB (the wonderful Tsinghua wind ensemble), probably because THUMB is such an awesome group of people to be a member of that it's hard to find any other place like it in the world. Honestly, I was quite disappointed after my first several rehearsals at JHU wind ensemble. People don't communicate very much with each other before or after rehearsals or during the intersessions, and the band board does not seem to take an effort to make the atmosphere more interactive. And perhaps overshadowed by the cutting-edge researches at JHU and the professional Peabody Institute, amateur music activities get so little attention from the school that the band is facing with financial problem this year. (BTW, that's the main reason why food served at today's concert was not so delicious. Sorry to you guys!) The university pep band is facing similar, if not more serious, shortage of "renqi" (Chinese for human energy). Only ten people or so play on the pep band regularly. When JHU's football team plays away game at those less "nerdy" universities, the small pep band is often overwhelmed by the much larger and more organized marching bands (like the one I saw in Gettysburg College).

Because of these superficially depressing facts, I thought about quitting on and off for a while. However, I was not determined enough to stop playing the tuba after playing it for > 12 years in a row. So I stuck on. In this semester, my feeling toward the band gradually changes, partly because I get more familiar with the band members. I begin to realize that the love for music of my peer musicians are as strong and pure as that in THUMB. Overall, the music skill is higher than most school bands in China. There are some really good players like David who played horn solo today and is able to tell which classical piece I am playing casually after hearing the first several notes, and like Tom the semi-professional Alto Sax. Drake, the conductor, is a very lively and interesting person and an experience conductor for school bands. My fellow tubaist, Caitlin, also plays very well (perhaps the best fellow tuba I have played with). Many other good things revealed to me as I stuck longer with the band, and the fun is coming back. Things which appear insipid can be actually fun if you have a right attitude toward them, especially after you have spent enough time. I guess that's the reason why it was possible for "old" people like Les, the great baritone player, to remain in the band for > 30 years.

So, this semester is a turning point in my career of amateur tuba playing. And because of you my dear audience, this concert was an great conclusion of it. You really made a difference in my life. Thank you!