A vicar was travelling on the train one day when a scientist happened to sit next to him. The scientist was an astronomer, and he smiled as he saw the vicar reading his Bible. He said, condescendingly, “I like to think that religion can be summed up by the words, ‘Do unto others as you would have them do unto you’”. The vicar, having discovered the scientist’s profession, replied, “Yes, and I like to think that astronomy can be summed up by the words, ‘Twinkle, twinkle, little star, how I wonder what you are’”.