Fulton dreamed of a steam-powered boat in the late eighteenth century, and while in France he designed and built a working vessel to run on the Seine. However, as he built the steam-driven Clermont in 1806 and 1807 in the United States to run on the Hudson River, a good many people scoffed at his project. Financial backers were few.
But at the launch of the 5-mph Clermont, people who had doubted his invention suddenly realized how insightful and brilliant it was. As Scientific American reports in 1846, “The jeers of the ignorant, who had neither sense nor feeling to suppress their contemptuous ridicule and rude jokes, were silenced for a moment by a vulgar astonishment, which deprived them of the power of utterance, till the triumph of genius extorted from the incredulous multitude which crowded the shores, shouts and acclamations of congratulation and applause.”* The offices of the magazine were, by the way, appropriately located on Fulton Street in New York.
There will always be doubters and scoffers. Build your boat.
* Scientific American, Vol. 2, No. 1. Online at http://www.gutenberg.org/files/27867/27867-h/27867-h.htm#spring