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It Was Fun

It Was Fun. While It Lasted. It Wasn't Much Fun. 1959, Moscow (USSR), M.Sc. Thesis. I was a computer. It Was Fun. 1960, Manchester (UK), Mercury. When love prevails Logic fails So the computer Was made neuter. It Was Fun. Computing meteor stream orbits. It Was Fun.

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It Was Fun

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  1. It Was Fun While It Lasted

  2. It Wasn't Much Fun 1959, Moscow (USSR), M.Sc. Thesis I was a computer

  3. It Was Fun 1960, Manchester (UK), Mercury When love prevails Logic fails So the computer Was made neuter

  4. It Was Fun Computing meteor stream orbits

  5. It Was Fun Running simulations of meteor swarm’s evolution

  6. It Was a Mistake I thought thecomputer was for computing (Just as Aristotle thought brain was for cooling blood)

  7. But it took me long time to see the light First I thought computers were too difficult to program

  8. But it took me long time to see the light So I wrote compilers KLIPA, ALGOL-60

  9. But it took me long time to see the light Then I thought running programs on computers was too messy

  10. But it took me long time to see the light So I wrote an operating system SODA

  11. But it took me long time to see the light Then I thought something was amiss with the data

  12. But it took me long time to see the light So I played with data structures

  13. And I’ve sinned For five long years I workedin the industry. Directing the transfer of OS/360 to Polish-made RIAD computers.

  14. Much later (1983, Dublin) Responding to an invited paper I said: Fred Brooks is a hard act to follow: I know, I’ve lifted the OS/360!

  15. Then I thought I saw the light Computer is for executing programs!

  16. Programming methodology Structured programming (programming structures) GOTO considered harmful

  17. Programming methodology Step-wise refinement Correctness

  18. Programming methodology Correctness, yes but what does it mean? With respect to ...

  19. Programming methodology Correctness wrt formal specification - „faultily faultless” - clear, but useless

  20. Programming methodology Specs ? Correctness Ill-defined relationship Reality Program

  21. Programming methodology Theory Satisfaction Satisfaction Well-defined relationship Model Model

  22. I was sure I saw the light It all reduces to theories. A good theory leads to good programs and satisfied customers. A poor theory hinders construction of good programs and makes customers weep.

  23. I was sure I saw the light Build theories of small domains, make program-models for them, then combine theories and programs shall jell together!

  24. I was sure I saw the light • But it ain’t necessarily so! • combining theories is difficult (and not always possible) • combining implementations is (nearly always) messy and often dangerous

  25. I was sure I saw the light Ithought that perhaps combinig little actions into larger systems should be done entirely without any notion of „time”, i.e even without anypredetermined notion of „follows”.

  26. I was sure I saw the light Thus the concept of doubly guarded command was born and (partially) explored

  27. But while I followed the light The world was changing became thesoup du jour

  28. In the new brave world Computers, becoming ever more numerous (and physically smaller), disappear behind services they provide.

  29. In the new brave world Computation has to be correct. Service has to be dependable.

  30. In the new brave world The mathematical, strict criterion of correctness is being replaced by a behavioural, loose criterion of dependability.

  31. In the new brave world All actors (people, machines and systems thereof) occasionally malfunction. This is not only accepted, but also expected.

  32. In the new brave world No-one really complains that Windowsâ is prone to crash, only that it crashes at an inopportune moment.

  33. In the new brave world Like no-one complains that tires occasionally go flat, only that it happens when we are particularly short of time.

  34. In the new brave world No-one is to blame and the guilt is subtly shifted to the „user”: If I only didn’t drive there, if I only didn’t press these two keys together! Or was it three?

  35. In the new brave world Every hour more users than babies are born. Each user soon becomes an expert at their specific fingering. Such an expertise quickly becomes an article of faith and an academic discipline.

  36. In the new brave world Particular fingerings turned articles of faith cum academic disciplines are invested.

  37. An aside, from Webster’s: • invest • - to array in the symbols of office and honor • to furnish with power or authority • to surround with troops or ships so as to prevent escape or entry • to commit money in order to earn a financial return

  38. In the new brave world In the ecumenical primordial ocean of Internet, growth is primarily by accretion of external grime. Reason is yet to be born: while no-one convinces, many try to catch.

  39. In the new brave world Correctness, rigour, mathematics of computing is pushed into an ever smaller and darker corner labelled „special concerns”.

  40. I have the feeling that Having witnessed the birth of computing science, I am witnessing its demise.

  41. While it lasted It certainly was fun!

  42. ?

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