Pradyumna: "Purport: In the human society, all over the world, there are millions and billions of men and women, and almost all of them are less intelligent because they have very little knowledge of the spirit soul."
Prabhupada: This is our challenge, that there are millions and trillions of men and women all over the world, but they're not at all intelligent. This is our challenge. So, the Krsna consciousness movement may be taken by others as crazy, or we challenge that "You are all crazy men." Therefore we have got a little book, "Who is Crazy?" Because they're thinking that "These shaven-headed boys and girls are crazy," but actually they are crazy. Because they have no intelligence. Why? They do not know what is spirit soul. This is the animal consciousness. Dogs, cats, they think that they are the body.
>>> Ref. VedaBase => Srimad-Bhagavatam 2.3.2-3 — Los Angeles, May 20, 1972