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Ph.D.答辯日

(See here for an English version)

從五六年前就開始想像的那一天,就這樣眨眼間過去了。現在回想起來許多細節仍歷歷在目:一大早烤箱帶來的香氣和悶熱、邊吃著Bagel邊和室友與拜訪的朋友看著跑跑卡丁車敗部復活賽、開車兇猛的Lyft司機、伏地挺身的痠痛。Ph.D.答辯的這一天就像是場籌備已久的舞台劇,一切幾乎都完美地照著劇本走下去(除了洗完澡後從練琴變成了驚喜派對),順暢到連當時的我都沒機會停下來幾秒,閉上眼感受當下心中的悸動。室友跟我說這一天的感覺,大概就跟結婚日差不多。身邊圍繞著這幾年來對我來說很重要的朋友們,我真是個幸福的人。

讀博士的這六年,當然是充滿著起起伏伏。在演講後招待會中的六道食物分別暗喻了每一年的心境轉變(感謝大學好友承昌一起想名稱):

初惑甜頭Seduced by sweetness(奶酪):第一年的我就像是個進入甜點店的小孩,看到什麼都想要吃上一口,肆無顧忌地吸取著各種養分。

品香嚐鮮Tasting the spices(Mysore pak):第二年有了許多開會和參加workshop的機會,去了西岸、英國、印度(在那邊嚐到了好吃的Mysore pak)和瑞士,見識到不同的研究風格和環境。

焦心力竭Burnt off passion(巴斯克蛋糕):第三年疫情的襲擊間接地讓我開始重新審視自己做的研究,並對理論CS的方法論產生疑問,對手中研究課題的熱情逐漸消磨。

拓邊展界Expanding the boundary(Pizza art):第四年我開始系統性地學習物理和腦神經科學,在研究合作和讀書會中擴展知識的邊界,重新找到對知識追求的熱忱。

揉煉完美Kneading for perfection(Sourdough):第五年我嘗試描繪出未來中長期的研究計畫,完美主義的精神讓我對自己有許多嚴厲的批判,徘徊在不同方法論之間,嘗試找出自己的一條路。

重省初心Rediscovering the roots(蒼蠅頭):第六年時我確定了接下來一步要踏往腦神經科學,同時也漸漸意識到科學方法中必然的不完美,因此漸漸放下對理論CS的批判,重新思考計算能夠扮演的角色。

在傍晚的驚喜派對中,好友L問到我在Ph.D.這幾年有沒有什麼遺憾。當下我很直覺地説,遺憾是一定會有的,就看主觀上我們是如何感受和接納它們。雖然乍聽之下是個故弄玄虛的場面話,但這樣的心態可是近幾年來我慢慢領悟到的道理。我當然很遺憾當年許下的Ph.D.三大目標(拿最佳論文獎、跑波士頓馬拉松、開鋼琴獨奏會)一個都沒有達成,當然很遺憾沒有好好珍惜身邊許多重要的人事物,當然也很遺憾答辯這天錯過了跟好多人講講話、拍照的機會。

但就像棒球教導我的,不管之前被三振了幾次,還是暴傳被教練罵個臭頭。每當站上了球場,過去發生的起起伏伏都是前進的養份,我要讓自己準備好到無論結果如何,都能夠笑著挺胸面對。

時間雖然看似連續地流逝著,但總是讓人在某些時刻能感受到強烈的分野。沈澱了半天後,在雨後前往琴房的途中,依然微涼的晚霞好像看起來不太一樣了。對許多人來說是場再平凡不過的答辯演講,對我來說既是完成了多年的想像,也總結了百轉千折的摸索之路,揭開了人生下一本書的序幕。