In time for Halloween… I found this on another site: (Quote)

DragonFruit · 61-69, M

Left-handedness was viewed as a sign of the devil....at one time, people were executed for being left-handed (for being witches or otherwise in league with the devil).
People would teach children to use their right hand rather than their left to protect them from being killed.

As a child, I heard that less than 5% of the population was left-handed, but the number has slowly increased because left-handed people are no longer killed.
Interestingly, most such traits appear in a 64/36 ratio (64% of dogs favor the right paw, 64% of cats favor the left paw, 64% of people can roll their tongue, etc )....so you would expect 36% of people to be natural left-handers but society forced that figure to be much lower (though it has been slowly rising, it's not likely to ever get back to 36% because of the persecution and societal norms forcing people for generations to not be left-handed.

DrWatson · 70-79, M

Before the era of modern hygiene, right-handed people performed unsanitary tasks with their left hands. So references to the left hand as evil, while "non inclusive", was not entirely arbitrary.

craig7 · 70-79, M

Yes,I recall learning the Latin origin of "sinister" at school - though of course the teacher did not mention anything of the ancient belief about left-handedness,as a number of my fellow students were left-handed writers.

hunkalove · 61-69, M

My father and brother were both left-handed. My father was the most horrible person I've ever known and my brother is a drug-dealing biker who can't stay out of prison.