Threads and tapestries
Threads are numerous, and travel down the histomap highway
in packs, like schools of fish. Along the way, threads
occasionally connect in little knots, creating a kind
of tapestry.
Knot of the day
Luca Pacioli, the leading mathematician
of the early Renaissance in Italy,
appeared in the algebra thread in Renaissance Urbino.
He was a student of Piero della
Francesca, and he wrote the most important algebra text
of the time, the
Summa de Arithmetica, Proportioni et Proportionalita
of 1494. Cf. (Katz, 1993) p. 319.
But in addition, he wrote a book on the golden thread:
De divina proportione, 1509, illustrated
by Leonardo. Cf. (Huntley, 1970) p. 25.
Ralph H. Abraham, 20 May 1996.