Explore learning, reasoning and ideas, with explanations that help readers ask better questions and examine how knowledge develops.
Learn how experts build mental models, use retrieval, spacing, interleaving and feedback—and why deliberate practice is not a 10,000-hour rule.
Sep 16, 2026 • 7 min readRead the discovery →New stories, explanations and research from Ideas & Learning.
A refrigerator does not manufacture cold. Its sealed vapour-compression system circulates a refrigerant through an evaporator, compressor, condenser and expansion device. The refrigerant absorbs…
Oct 14, 2026 • 3 min read
Smoke alarms detect airborne products of combustion rather than heat alone. Photoelectric alarms use a light source and sensor arranged so smoke particles scatter…
Oct 14, 2026 • 3 min read
Most basic electric kettles switch off when steam from boiling water travels through a channel to a thermostat near the base or handle. The…
Oct 14, 2026 • 3 min read
Residential smoke alarms usually detect particles made by combustion rather than flames themselves. Photoelectric alarms shine light through a dark sensing chamber and trigger…
Oct 13, 2026 • 3 min read
Automatic doors commonly use microwave radar to detect motion approaching the entrance, active infrared sensors to measure reflections in a monitored zone, or both.…
Oct 13, 2026 • 3 min read
Most click mechanical pencils use a spring-loaded three-jaw clutch. Pressing the button pushes the clutch forward and opens its jaws, allowing the graphite core…
Oct 13, 2026 • 3 min read
An induction cooktop sends alternating electric current through a coil beneath its glass surface. The coil creates a rapidly changing magnetic field, which induces…
Oct 11, 2026 • 3 min read
Returning to material over time usually produces more durable learning than packing the same practice into one sitting.
Sep 14, 2026 • 8 min read
Learn a strategic way to read scientific papers, from abstract and methods to figures, results, limitations, references and conflicts of interest.
Sep 12, 2026 • 7 min read
Returning to material over time usually produces more durable learning than packing the same practice into one sitting.
Sep 14, 2026 • 8 min read
Learn a strategic way to read scientific papers, from abstract and methods to figures, results, limitations, references and conflicts of interest.
Sep 12, 2026 • 7 min readOne remarkable idea at a time—nature, science, history and beyond.
