three in one cup,
but I drink to one name,
who am I, this night?
盃に 三つの名を飲む 今宵かな
sakazuki ni mitsu no na o nomu koyoi kana

Oct. 23, 1685, Edo
Everyone likes a good riddle. So who was Matsuo Basho toasting?
On this date in Japanese history, Yamaga Sokō, original name Yamaga Takasuke died. He was a military strategist, Confucian philosopher, and originator of what would become the Bushido Code by which all Samurai would operate.
Three in One conjures up an image of the Holy Trinity, the Father, The Son, and the Holy Spirit. Three for One, makes one also think Alexandre Dumas‘ 19th century novel Three Musketeers, who proclaimed, “Un pour tous, tous pour un. (One for all, and all for one.)”
Sakazuki Takasuke!
No, Basho likely had in mind Takasuke in offering up Sakazuki, a ceremonial cup of wine. This is speculation, but it fits nicely. Basho being descended from a Samurai family would want to honor another. Takasuke Sakazuki! Takasuke Sakazuki! Takasuke Sakazuki! The honorific was said three times.
Li Bai
Matsuo Basho also had in mind 8th century Chinese poet Li Bai (太白,744–762). He of many titles including the Transcendent Poet, Banished Immortal, and Green Lotus House Warrior. The first for his skill as a poet, the second for his prodigious drinking, and the third as an artist.
Basho’s haiku is a response to Li Bai’s well-known poem Under the Moon, Drinking Alone.
In the midst of flowers, with one jug of wine
Drinking alone, and no one else,
I offer up my cup, to the bright moon
My shadows and I, a party of three.

Three
Why three? Things that come in threes are funnier, interesting, and more memorable. Comedians, magicians, and poets know to set up a sequence with three short lines, then the punch line. Three is mystical. The Holy Trinity, as I’ve said. It also creates a unique pattern and a relationship that the brain can understand. The Three Blind Mice, The Three Little Pigs, The Three Stooges. Three is also an odd number, the first Prime number, if one excludes the number “one.” Two fit together nicely, but three rarely do.
Basho explains
By way of explanation, Basho’s haiku came at gathering for moon-viewing (観月) at his home in the fall of 1685. He he had returned to Edo and his Banana Hut after the first of his wanderings. Present were three friends all named Shichiroubei. No doubt Basho founds some humor in the homonyms, zuki, as in cup, and tsuki, moon; as well as the visual similarity of the flat circular cup and the circular full moon.
Basho ends his haiku alliteratively with koyoi kana, 今宵, literally, this night, but also a question, as in, who am I?
Sakazuki
Gentle Reader, nomu, 飲む, let’s drink: Akemashite omedeto gozaimasu
