It is more from carelessness about truth than from intentionally lying that there is so much falsehood in the world.

Most false things in circulation were not invented by liars. They were repeated by people who did not check, who liked the sound of it, who half remembered, who were in a hurry and wanted to sound informed. Deliberate deception is rare and expensive; casual indifference to accuracy is free, and it does far more of the damage.

The remedy is unglamorous and available: before you pass something on, notice whether you actually know it. Saying that you are not sure costs a small amount of social standing and prevents a large amount of nonsense. It also makes the things you do assert worth more.