I don’t think the wheel is a simple invention by any stretch of the imagination, in fact it is quite a piece of technology not only to think of it but to make, even the first stone versions, but placing a space between individual words is probably the simplest thing one could ever think of, but in the days when parchments and papers took weeks to make and space was at a premium on stelae and scrolls, spaces were unheard of yet the way in which the eye picks up on white or clear space in written text, space is vital to understanding.
If you look at old paintings you can see Latin inscriptions are written until the line ends and carried on with no regard to breaking up the words. With books the right to play with the text arose and punctuation – which grew out of the dots and lines in Latin inscriptions – began to take on life.
It is this transference of meaning and ease of understanding and reading that is at the heart of grammar and punctuation, and indeed of typesetting. All the ways and means of making an effect in the brain of the reader, conveying ideas and keeping their attention, are all there working away and every dot and comma becomes important but nothing is more important than the empty spaces.