Dr. Shinya Yamanaka, 2012 Nobel Prize winner in Physiology or Medicine, the initiator of all-around (iPS) cells told a recently-held public symposium, quote:
“I’m often asked by many people: ‘You are happy that you've won the Nobel Prize, aren’t you?’ But I tell them that everything in life is just like 'Saioh ga uma' (塞翁が馬) – Old Sai’s horse. I was unsuccessful as an orthopedic surgeon, but luckily I found my way in molecular biology." – The Asahi, Oct.4, 2014 issue
“Life is like Old Sai’s horse” is a popular Japanese saying, which is based on the story described in Chinese classic literature written by 准南子- Huai nan zi, the ancient Chinese monarch of Huian nam in circ. BC 135.
The story begins when a horse kept by an old man living near a fort (塞翁) ran away one day. All the neighbors came to console the old man, but he told them not to worry. Ｍonths later, Old Sai's horse came back, accompanied by a faster horse. Old Sai’s son loved horse riding. He fell off and broke a leg one day while riding the faster horse. The son became lame. Villagers consoled Old Sai for his son's misfortune. But Old Sai said, “Don’t worry. There’ll be a good day after a bad day.” A year later, the village was attacked by the Hu Country's army, and the fort was destroyed. All the young men of the village were called to the military. Nine out of ten of them died during the war. Old Sai’s son was exempted from conscription because he was lame, so he was unharmed. The story goes on and on describing the happenings of a thread of fortune and misfortune of his family in turn.
So when we say “It’s Saioh ga uma -塞翁が馬(塞翁失馬)” in Japanese (Chinese), we mean that life changes, happiness (success) and unhappiness (failure) rotate. We needn’t to be too glad and too sad at each instance.
Though “the ebb and flow” occurs to my mind as a possibility, I’m not sure of whether it fits the concept. Are there more suitable English equivalents to “Old Sai’s horse”?