3.10 A final word – analogue and digital worlds

So there we have it. On the one hand is our world, an analogue world – a world of light and sound, of taste and touch. On the other side of the boundary is the computer's digital world – a bleak world of binary numbers.

Before I leave the topic, though, I should point out that some of the points I've made may be controversial.

For a start, it's not entirely clear whether the world we inhabit is fundamentally analogue. Quantum theory tells us, for instance, that quantities like light are made up of tiny packets (quanta) of energy. This means that the intensity of a source of light may not vary continuously, but will go up or down in discrete (quantum) steps. Some theories suggest that forces like gravity, and even space itself, may be made up of tiny quanta.

Nor is it certain whether the human brain is an analogue or a digital device. Certainly, the brain is quite different in structure and function from a digital machine. Lazy comparisons between the human mind and a computer are completely misleading. However, there is still argument about whether, at some level, the brain functions like a digital device.

These are all esoteric debates, though, and beyond the scope of this course. Let's now return to our main theme and cross the boundary.