@Kariuki, @steve - Hmmm.... - disease causes death, time causes death - 'in the midst of life, we are in death' - hence my 'generation' estimate of 30 years. The 'how' of it is irrelevant ;) If we allow for concurrent generations (which is normally the case - at least three) then the total should be 2^10 + 2^9 + 2^8 - so I think I was being conservative. @Brian - perhaps I was not precise in my wording, but your great-great-grandfather was born from the union of one lucky sperm, with one egg from one of his father's many wives ;) - everybody is the child of one biological father, and one biological mother - so your polygamous spanner, thrown into the procreational works is irrelevant ;) @Ken - AHHHHH!!! - give that man a coconut! *there's* the flaw in the reasoning!!! (but now you've spoiled the fun! ;) ) @Moto... - Binary existed since time immemorial - waaay before humans walked this earth. It took about 4 billion years (or 6000, if you believe certain theological arguments ;) ) until the French had to spoil everything with their stupid 'decimal' system! :D Tune in next time for more argumentative paradoxical rumination.... -- Tony