Unto the pure, all things are pure

It seems that most people, especially present day young ones, have problems understanding my Apollo 11 illustration .  I will try again with another example. When the most well-known bank in my city had a million customers, it had 50+ branches.  Almost every customer operated a savings account where each was given a savings book.  Every deposit or withdrawal transaction was printed as a one-line entry in the book with the latest balance in the second last column.  (The last column was a comments field.) Every teller in the branch had an IBM terminal.  Customers would fill up and sign a form to withdraw money, or just present cash to deposit.  The teller would open the savings book to the page where the last entry was and insert the book into the printer next to the terminal.  She would push the book all the way in.  When she hit the key to print, the central mainframe computer would send out the exact number of line-feeds so that the latest transaction would be printed nicely just

Probably something like 80% to 90% of the new found computing power goes into the graphical user interface. This is on personal computers as well as mobile phones. The sleek graphics painted in a window that we take for granted require billions and billions of computing cycles, repeating and repeating every time something on screen changes. The graphical UI is obviously a great enabler. It allows lay people to use the computer where previously only trained professionals could. However, do not let this be a distraction. The fact that a small fraction of an iPhone powered the complete operations of a bank or sent men to the moon and back cannot be erased. And it is repeatable, with great ease.