How did an art critic john canedy influence the opinions of art lovers and buyers in the 1960s in the 1970s

He made it more acceptable to enjoy and purchase different kinds of art.

He accused supporters of the New York school of Abstract Expressionism (the dominant idiom of the day), of lowering the standards of art. While he acknowledged the talents of many abstract artists of the time, he said that some of them were only interested in making money. They, he argued, presented many works of substandard art. And he also accused many in the mainstream art establishment of trying to trick people into accepting substandard art. He was attacked by many in the art establishment, but he also received support from several well-known artists and critics.

Generally spontaneous human combustion is something that still bewilders some, human combustion happens very rarely and doesn't affect the surrounding areas, so unless you want to set your self on fire, human combustion will remain spontaneous and very rare.