He proposed that there were seven, including music, linguistic, kinesthetic, math, etc., which I remember seeming eerily similar to the classic seven liberal arts.
(nothing new under the sun)
Eventually, the list grew from seven and an oft-cited "eighth intelligence" was termed the "Naturalist Intelligence".
From an ASCD article:
Naturalist intelligence designates the human ability to discriminate among living things (plants, animals) as well as sensitivity to other features of the natural world (clouds, rock configurations). This ability was clearly of value in our evolutionary past as hunters, gatherers, and farmers; it continues to be central in such roles as botanist or chef. I also speculate that much of our consumer society exploits the naturalist intelligences, which can be mobilized in the discrimination among cars, sneakers, kinds of makeup, and the like. The kind of pattern recognition valued in certain of the sciences may also draw upon naturalist intelligence.
Not that Gardner is the supreme being on matters like this, he merely coined the phrase, but he speaks to the Naturalist in the same ASCD article, here:
http://tinyurl.com/8th4CreekDog
Now, as the naturalist view of things can be a scary way of looking at the world, and challenge many conventions, social and religious, it's easy to imaging how many could be threatened by such ideas as communing with nature, womanhood being the powerful thing that it is, relationships with nature being greater than relationships to a patriarchy. And, further, it's easy to imagine the threat presented by powerful women who channel their eighth intelligence becoming the targets of harassment, lawsuits, and having their property taken from them.
I hope this helps.