Quote: "Only a complete fool makes accusations based on what another person has told them. Don't assume everything you hear to be true, and never accuse without knowing all the facts or both sides of the story. The best option is to stay silent if you don't witness something yourself." 

Articles: 

https://www.harleytherapy.co.uk/counselling/making-assumptions.htm

https://www.recoverywarriors.com/negative-assumptions/