Sources and studies
Our inspirations
Two sources guide us: the tradition, which has observed the soul for centuries, and research, which measures today what reading and writing do to the mind.
In the tradition
Shukr in three movements: humility in the heart, praise on the tongue, obedience in the limbs.
Source — Ibn al-Qayyim (691–751 AH / 1292–1350), Madārij al-sālikīn. It is the clearest description the tradition gives — SHUKR, p. 13.
The limit — Recognize, express, act: the three stages of our books are today's wording of a teaching passed down for centuries. We did not invent it, we translated it.
Patience and gratitude have long been taught together.
Source — Al-Ghazālī (450–505 AH / 1058–1111) devotes a whole book of the Iḥyāʾ ʿUlūm al-Dīn to them. Two centuries later, Ibn al-Qayyim writes a treatise whose title holds them together: “the Provision of the Patient and the Treasure of the Grateful” — SHUKR, pp. 13–14.
In the ninth century, a physician was already describing anxiety, sadness and obsessive thoughts.
Source — Abū Zayd al-Balkhī (850–934), Maṣāliḥ al-Abdān wa al-Anfus, translated and annotated by Malik Badri, Gutenberg Press, 2013. His manuscript, eleven centuries old, now rests in the Ayasofya Library in Istanbul.
The limit — He proposed acting on thoughts — restructuring, gradual exposure — not writing them down. We cite him for what a tradition was able to observe, not to make our books his heirs.
In the research
What you produce, you remember. What you read, you merely recognise.
Source — Slamecka & Graf, 1978 — the generation effect, established across five experiments.
Testing yourself loses in the short term. And wins in the long term.
Source — Roediger & Karpicke, 2006 — the testing effect, one of the most robust findings in the psychology of learning. After five minutes, rereading wins. After two days and after a week, testing wins clearly.
The limit — The students who reread felt more confident. That is precisely the illusion the method sets out to break.
On screen, comprehension drops. And the gap has widened over the years.
Source — Delgado, Vargas, Ackerman & Salmerón, 2018 — a meta-analysis of 54 studies and over 170,000 participants. The paper advantage grows across the period analysed: this is not a generational matter, and digital natives are no exception.
The limit — The gap concerns expository texts, the ones read in order to learn. For narrative texts, another meta-analysis finds no difference. We do not claim paper always wins.
Nearly half a million readers: digital leisure reading barely improves comprehension.
Source — Altamura, Vargas & Salmerón, Review of Educational Research — 469,564 participants. The effect is close to nil, where print reading habits show medium effects. Among younger readers the relationship is even negative.
The limit — This is a correlation, not proof of cause. Reading a great deal on screen does not mechanically damage comprehension: it simply does not build it, as print does.
Writing by hand engages the brain more widely than typing.
Source — Van der Weel & Van der Meer, 2024 — high-density EEG, 256 sensors.
The limit — This study measures brain connectivity, not learning outcomes. It received a published critical commentary in the same journal. We cite it for what it shows, not for what we would like it to say.
Our rule
Every claim carries its source. And its limit.
A remark, a reading, a source to share? Write to us — this page improves with what people bring to it.
A book is not a therapy, and we promise no medical benefit.