Counting sheep as a way to fall asleep appears in writing many centuries old.

The longer version

The image of sheep hopping a fence as a route to sleep appears in medieval and early modern writing, and the trick depends on mild, repetitive mental work that crowds out more stimulating thoughts. The method works by occupying attention with something monotonous and slightly boring rather than by any property of the animals.

The choice of sheep probably reflects pastoral life more than anything about the animal. Similar repetitive distractions, from reciting verse to imagining slow walking, show up across cultures. Whether such methods actually speed sleep onset is not well established, and trials suggest that vivid imagined scenes work against sleep precisely because they keep the mind engaged.

Where this entry sits

This collection gathers curious details about sleeping and dreaming, from nightly brain stages and body clocks to naps, yawns and unusual animal habits. It also covers how bedtime customs have changed across centuries, without offering any advice. The full list sits on the Sleep and Dreams page, where every entry is listed in order.