The problem of defining exactly what is meant by the signal velocity, which cropped up as long ago as 1907, has not been solved.

The switch from 'steam engines' to 'heat engines' signals the transition from engineering practice to theoretical science.

As every bookie knows instinctively, a number such as reliability - a qualitative rather than a quantitative measure - is needed to make the valuation of information practically useful.

The smell of subjectivity clings to the mechanical definition of complexity as stubbornly as it sticks to the definition of information.

Time has been called God's way of making sure that everything doesn't happen at once. In the same spirit, noise is Nature's way of making sure that we don't find out everything that happens. Noise, in short, is the protector of information.

If you don't understand something, break it apart; reduce it to its components. Since they are simpler than the whole,you have a much better chance of understanding them; and when you have succeeded in doing that, put the whole thing back together again.

We don't know what energy is, any more than we know what information is, but as a now robust scientific concept we can describe it in precise mathematical terms, and as a commodity we can measure, market, regulate and tax it.