What is the Limit of Knowledge?

In my London childhood, a horse-drawn wagon delivered milk each day in glass bottles with the cream risen to the top in a visible layer. Sparrows had learned to peck through the foil caps and gorge on the prize.

My first computer used magnets the shape of a doughnut and smaller than an apple pip for memory, each holding one bit of data, each with three wires threaded through it to read and change its magnetism. I say my computer, but it belonged to an international company, occupied a whole...