M♪o 之學習筆記本《丑》控制︰【白金西】時回流反

錦瑟‧李商隱

錦瑟無端五十弦，一弦一柱思華年。
莊生曉夢迷蝴蝶，望帝春心託杜鵑。
滄海月明珠有淚，藍田日暖玉生煙。
此情可待成追憶，只是當時已惘然。

白金西︰所謂明智，是能將事後之明﹐用於臨事之前。當真為『回反』者也。

派︰西有『葉慈』者，浪漫賦神秘，善寫《奧義詩》，其詞雖簡易，其意實難測︰

The Song of Wandering Aengus
W.B. Yeats （1899）

I went out to the hazel wood,
Because a fire was in my head,
And cut and peeled a hazel wand,
And hooked a berry to a thread;
And when white moths were on the wing,
And moth-like stars were flickering out,
I dropped the berry in a stream
And caught a little silver trout.

When I had laid it on the floor
I went to blow the fire aflame,
But something rustled on the floor,
And some one called me by my name:
It had become a glimmering girl
With apple blossom in her hair
Who called me by my name and ran
And faded through the brightening air.

Though I am old with wandering
Through hollow lands and hilly lands,
I will find out where she has gone,
And kiss her lips and take her hands;
And walk among long dappled grass,
And pluck till time and times are done
The silver apples of the moon,
The golden apples of the sun.

漂泊的安格絲之歌
葉慈

我前往榛子林
顱腔熱火在呼喚
切剝榛枝正嫩
漿果鉤住了思緒
忽而，白蛾乘羽翼
星兒彷彿蠹飛影搖曳
拋莓入溪後
恰獲一尾小銀鮭

任之將之委諸地
反身吹燃燄
簌簌有聲來處響
誰人在呼喚我之名
怎想它早已化作微光少女
蘋果花，隨髮絲綻放
她既呼喚我之名又奔棄
漸淡入，黎明空靈中

儘管年華因著漂泊老
穿越山谷和山丘
誓將找到她鄉去時路
吻芳唇，攜伊之手
漫步長斑青草間
採綠意，直至時盡次不再
月月銀林檎
日日金蘋果

☿ 眉批︰拋漿果，得銀鮭？甚可疑？『反身吹燃燄』心欲何為？『顱內火』，林中之榛有何益？何事『切剝』榛嫩枝？哪處飛來了『白娥』？意念藏心底，時流往復反，意象難分明，誰知他說的是過去還是未來！若講『命中注定』，所謂伊人又豈該在『夢之鄉』！怕卻是『當面錯過』！！那將怎能夠不為著此『呼喚』，去漂泊天之涯地之角的呢？？

生︰回反因果知幾何，有話說︰

Feedback

Feedback occurs when outputs of a system are “fed back” as inputs as part of a chain of cause-and-effect that forms a circuit or loop.^[2] The system can then be said to “feed back” into itself. The notion of ’cause-and-effect’ has to be handled carefully when applied to feedback systems:

“Simple causal reasoning about a feedback system is difficult because the first system influences the second and second system influences the first, leading to a circular argument. This makes reasoning based upon cause and effect tricky, and it is necessary to analyze the system as a whole.” ^[3]

In this context, the term “feedback” has also been used as an abbreviation for:

Feedback signal – the conveyance of information fed back from an output, or measurement, to an input, or effector, that affects the system.
Feedback loop – the closed path made up of the system itself and the path that transmits the feedback about the system from its origin (for example, a sensor) to its destination (for example, an actuator).
Negative feedback – the case where the fed-back information acts to control or regulate a system by opposing changes in the output or measurement.

碼︰有家習。