The quote means that, if people do not show respect towards other people, creatures, and cultures, they are no different than the lowliest animals of the earth. Confucius was a Chinese philosopher, politician, and teacher. His believed strongly in respect of elders and the traditions of family. He was influential during the Spring and Autumn periods of China but continues to be very influential today. Because it is written by Confucius, one can assume that this quote belongs to the beliefs of Confucianism. As for agreeing or disagreeing, my opinions are not yours, so you should write that yourself. :)