Wanting something to be true doesn’t make it true – but sometimes, desperately wanting something to be true pays off. Sometimes because you’re actually right (by luck), and that passion helps you put in the work required to establish it, sometimes because your deluded quest ends up finding something else of actual value – sometimes far more valuable than what you were looking for.
Columbus wanted to sail to the Indies. Since the earth was 25,000 miles around, that was impractical – the trip would be around 10,000 miles one-way. Too far. So Columbus believed whatever he had to believe in order to make the voyage practical. He shopped around for a smaller estimate of the size of the Earth: the one he picked, about 18,000 miles, appears to have been the lowest ever made. Only the Spanish monarchs were rubes enough to support him. All wrong, but it led to the biggest success in the last millenium,
Kepler conceived the delightfully loony notion that the orbits of the planets could be explained by nesting the Platonic solids, each encased in a sphere, within one another. Five Platonic solids, six planets: obvious! Hard to fit Uranus into this, but it wasn’t definitively discovered until after Kepler’s death. Anyhow, his loony idea somehow led to his discovery of Kepler’s three laws – quite a haul.
On the other hand, in the social sciences, this seems to be the dominant theme: most of their tenets are what the practitioners wish were true. So far, no New World, no three laws as byproducts.