Here's the thing though. If I say "I think, therefore I am" and someone points out that was said by Descartes in 1637, does that mean I didn't say it, whether or not I coined the expression?
No, it only means that you didn't come up with the expression. A more accurate phrasing would be "Your presupposition that I think I said 'I think, therefore I am' is spurious, because I
know I said 'I think, therefore I am', but I also know I didn't come up that wonderful and incomparable expression, so you owe me an apology. Or, at least, a Coke."
The phrase "Bob's your uncle" is believed to have originated from the 1887 appointment of Arthur Balfour to Chief Secretary for Ireland by his uncle, Prime Minister Robert Cecil, 3rd Marquess of Salisbury. This is the most commonly cited origin story: that an act of blatant nepotism led to the saying, implying Balfour's success came easily due to his influential uncle.
Some critics have pointed out that the first documented use of the phrase in print is from the 1920s or 1930s (decades after the 1887 appointment). But to that, I say: so what? If the 1887 story is right, the phrase was in common usage for decades before it was used in print. After all, no-one just writes down a common idiom if it wasn't in common usage, first.
Speaking of famous bobs, Sir Robert Peel is considered the father of modern policing because he established the London Metropolitan Police in 1829, thus creating the first full-time force separate from the military. His work led to the creation of the "Peelian Principles," a set of nine principles that guide police work, emphasizing crime prevention, the importance of public trust, and the use of force only as a last resort. His name gave us both "Peelers" and "bobbies" as nicknames for British police officers.
One last bob: the future Edward VII (nicknamed 'Bertie') enjoyed the company of the cockney prostitute, Rosa Lewis. Deprived of a trysting-place, Bertie once went for a very long drive in a closed hackney coach with Rosa. At the end of the journey, Bertie gave the cabbie a shilling.
"What's this bleedin' bob for?' asked the cabbie, who didn't recognize the Prince of Wales, and was not best pleased. 'It's your fare, my man,' said Bertie.
'A bleedin' bob for two hours' drive and ten miles?!' the cabbie yelled. Luckily, at this moment Rosa leant forward and gave the cabbie two sovereigns. This changed his tune. 'I knowed you were a lady as soon as I seen you,' said the driver to Rosa, 'but where d'you pick 'im up.' The future King of England loved this story and often told it against himself.