I used to have very keen visual perceptions, I once managed to spot, amid the bubbling current and rescue a friends floating contact lens, that she had lost about 50 ft upstream from where I was crouched at the river. Everyone thought I was joking when I said I found it.

On the other hand, I have never found a four leaf clover in my life, while my daughter, when she was small, could find in our little patch of lawn, at least one a week.