These are from Sloane's lateral thinking book (see previous posting)
Simon Newcomb (1835 - 1909) a leading US astronomer. He declared that flight by heavier-than-air objects was completely impossible. Even after the Wright brothers first flight he claimed that aeroplanes were impractical and worthless.
Dr Dionysius (1793 - 1859) professor of natural history and astronomy at London University. Warned that railway trains traveling at speed would asphyxiate their passengers through lack of air. Also, that steamships could not cross the Atlantic because the would need more coal than they could carry.
Ernst Werner von Siemens (1816 -1 1892) German engineer of the Siemens company. Declare that 'electric light will never take the place of gas.'
Charles Duell, commissioner of the US patents office said in 1899 that 'everything that can be invented has been invented.'
HM Warner of Warner brothers said in 1927 'who the hell wants to hear actors talk?'
Albert Einstein said in 1932 'there is not the slightest indication that nuclear energy will ever be obtainable.'
John Langdon Davies, fellow of the royal anthropological institute suggested in 1936 that 'by 1960 work will be limited to 3 hours a day.'
Ken Olson, CEO of DEC said in 1977 'there is no reason anyone would want a computer in their home.'
Gill Gates stated in 1981 '640k ought to be enough for anybody.'