Every autumn, millions of leaves fall in a single British wood. Nobody counts them. Nobody could. The Qur'an makes a quiet claim about every one: “Not a leaf falls but He knows it” (6:59).
al-ʿAlīm is the All-Knowing. It is one of the Names that appears most often in the Qur'an. We live in an age of information; we carry most of human knowledge in our pockets. This episode asks how much we really know, and what knowing everything would actually mean.
Start with what we know
Then take away everything it needs. What is left is not a bigger version of us. It is the Name.
Episode 1
In us
Your brain has about 86 billion neurons (Azevedo and others, 2009), each linked to thousands of others. In 2016 scientists at the Salk Institute estimated that its memory capacity could be at least a petabyte, roughly the same as the whole World Wide Web at the time (Bartol and others, eLife). It is the most complex object we know of. And yet we forget most of what happens to us, misremember much of the rest, and know almost nothing about what our own cells are doing right now. Even the best human mind knows a small corner of the world, for a few decades, from one point of view.
Episode 2
In nature
Clark's nutcracker, a crow-like bird of the mountains of North America, hides tens of thousands of pine seeds each autumn in thousands of separate spots across the hillsides, then digs many of them up again through the winter, sometimes under snow, months later (Vander Wall and Balda, 1977). Its memory for places outperforms ours by far. But it still forgets a share of its caches, and those forgotten seeds become the next forest. Even the best memory in nature is memory of where, not of why, and some is always lost.
Episode 3
At our best
In 2022, the Frontier supercomputer in the United States became the first to pass a billion billion calculations a second, and machines since have gone further (TOP500). Data centres now hold more information than anyone could read in a million lifetimes. It looks like knowledge without limit. But a computer knows only what has been measured and stored. It cannot know a fact no sensor caught, a thought no one wrote down, or a leaf that fell unrecorded in a wood. It knows data, not things, and it understands neither.
Episode 4
The Break
Take away forgetting, one point of view, the sensor, the stored record, the gap between data and understanding. Every knower we know knows a little, from outside, after the event. al-ʿAlīm is not a bigger database; He knows each thing as it is, from within, before and after, without learning. “With Him are the keys of the unseen; no one knows them but He. He knows what is on land and in the sea. Not a leaf falls but He knows it” (Qur'an 6:59, our rendering).
The Qur'an tells how Moses (peace be upon him) went on a journey to meet a servant of God who had been given a special kind of knowledge (18:60-82). Tradition names him al-Khiḍr. The journey happened, the Prophet Muhammad (peace be upon him) explained, because Moses (peace be upon him) had once been asked who was the most knowledgeable person on earth, and had answered: “I am.” God told him that there was someone who knew what he did not.
The two of them boarded a boat together. As they sat at the edge, a small bird landed on the side of the boat and dipped its beak once or twice into the sea.
al-Khiḍr turned to Moses (peace be upon him) and said: “Moses, my knowledge and your knowledge, compared with God's knowledge, are no more than what this bird has taken from the sea with its beak” (Bukhari 4725).
The rest of the journey taught Moses (peace be upon him) the same lesson three times over: things that looked wrong at first turned out to have reasons he could not see. That is why Muslim scholars, even the greatest, often end an answer with two words: Allāhu aʿlam, “God knows best”.
What each faith says
Judaism
“O LORD, Thou hast searched me, and known me. Thou knowest my downsitting and mine uprising, Thou understandest my thought afar off.”
In the song of Hannah, a mother who had prayed for a child, God is called “a God of knowledge”. Psalm 139 describes being known completely, every word on the tongue before it is spoken, as something both humbling and comforting.
Jewish thinkers, especially Maimonides, wrestled with how God's complete knowledge fits with human free choice, and concluded that God's knowledge is unlike ours: it does not force what it knows.
Christianity
“There is no creature that is hidden from his sight, but all things are naked and laid open before the eyes of him to whom we must give an account.”
Christians call God omniscient: knowing all things. Paul, after a long argument about God's ways in history, breaks off in wonder: “Oh the depth of the riches both of the wisdom and the knowledge of God!” (Romans 11:33).
The letter to the Hebrews says nothing is hidden from Him. For many Christians this is a call to honesty, and a comfort: they are fully known and still loved.
Islam
“They said: Glory be to You; we have no knowledge except what You have taught us. You are the All-Knowing, the All-Wise.”
al-ʿAlīm occurs over 150 times in the Qur'an. Muslim theologians described knowledge as an eternal attribute of God: He does not learn, discover or forget, and His knowledge covers what was, what is, what will be and what would have been. The angels themselves say: “We have no knowledge except what You have taught us” (2:32).
For people, the Name is a double invitation: to seek knowledge, and to be humble about it. The Qur'an teaches the prayer: “My Lord, increase me in knowledge” (20:114).
Same and different
Jews, Christians and Muslims all believe God knows everything, including our thoughts, and all three have thinkers who worked hard on how that fits with human freedom. Psalm 139, Hebrews 4:13 and Qur'an 6:59 say almost the same thing in three voices. The differences are mostly about how God makes His knowledge known: through the Torah and prophets, through Christ, or through the Qur'an. All three encourage the habit of the scholar who says, “God knows best.”
A moment to reflect
How does it feel to think that someone knows everything about you?
What is something you once felt sure of and turned out to be wrong about?
Where would you like your knowledge to grow, and why?
Watch
Watch on YouTube ↗ · plays here on the live site; YouTube without tracking until you press play
BrainFacts.org on how many neurons are really in the brain: the ‘In us’ rung.
Watch on YouTube ↗ · plays here on the live site; YouTube without tracking until you press play
Cornell on the secret of Clark's nutcrackers and their memory: the ‘In nature’ rung.
Watch on YouTube ↗ · plays here on the live site; YouTube without tracking until you press play
Why trees drop their leaves, and how many fall: the hook of this episode.
Do it together
families / schoolsThe leaf count
In autumn, mark out a one-metre square under a tree and try to count the leaves that fall on it in ten minutes. Multiply up for the whole tree, then the wood. Read Qur'an 6:59 and Psalm 139:1-4 together.
faith groups / neighboursGod knows best
Ask each person to share one question they have never been able to answer. Do not try to solve them. End by talking about what it means to say Allāhu aʿlam, or ‘only God knows’, honestly rather than as a way of ending a conversation.
Episode 1
