The light of the day · Saturday 5 September
A dark room with a pinhole gave the camera its name
Make a small hole in the wall of a dark room and the scene outside appears on the opposite wall, upside down. The effect was noticed long before anyone explained it. It is described in the Chinese Mozi text around the fourth century BCE, and a Greek work handed down under Aristotle's name notes that gaps between leaves cast crescents on the ground during an eclipse. Ibn al-Haytham, in Cairo in the early eleventh century, turned it into an experiment. He set several lamps outside the aperture and showed their images stayed separate on the wall, which means light travels in straight lines and rays do not mix. His term was the dark room. Kepler put that into Latin in 1604 as camera obscura.
Ibn al-Haytham · Cairo, early eleventh century
Saturday 5 September 2026 · 22 Rabi al-Awwal 1448 AH
The word · The Qur'an
حَفْصٌ عَنْ عاصِم
Hafs an Asim
The reading found in most printed mushafs today, transmitted by Hafs from his teacher Asim of Kufa.
Hafs ibn Sulayman learned it from Asim ibn Abi an-Najud, whose chain runs back through the Companions to the Prophet. It spread with mass printing and is now the default across most of the Muslim world, which is why many readers assume it is the only way the Qur'an is read. Asim's other transmitter, Shu'bah, differs from Hafs in a modest number of places.
The Path · chapter 5 of 71
إدريس
Idris: Writing, Sewing, Stars
The first to write, sew clothes, and study the stars.
Truthfulness is the oldest credential of prophethood
The library
The whole library, free
No ads, no account, no tracking. Every room on the phone, under the thumb.