Up and down, big and small, left and right, wavy and straight. Opposites are the first pairs a toddler can hold in their head at once, and this board book gives them something to do with their hands while they work it out.

Each spread carries a printed trail. A child follows the arrow or traces the shape of the object with a fingertip, which turns an abstract idea into a movement they can repeat. It is the same principle behind a Montessori sandpaper letter, applied to a board book a two year old can operate alone.

The artwork comes from the We're Going on a Bear Hunt animated film, so the horse, the owl, the earthworm, the bulrushes and the bear himself all arrive already familiar to a child who has watched it. Recognition is what gets a toddler to open a book without prompting.

Twelve thick board pages, a square trim, rounded corners. It is small enough for the pushchair and short enough to finish in one sitting, which is exactly the length a two year old is willing to give you.

For a newborn rather than a toddler, the same idea arrives stripped back to three colors. Opposites from Baby's First Library sets each pair in flat black, white and red, which is all an eye a few weeks old can resolve.