I think what this person is trying to say (but said it poorly) was that Bonsai is art, therefore people who are creative and like to work with there hands are most often the people who practice this art. People need a creative perspective on things to really bring out the Bonsai "look" in a tree or shrub.
But since this is a "living art" there has to be some level of intelligence to be able to maintain the life of the plant. Like other people said in this thread, you have to know the species of tree to be able to maintain the life of it. This is where "intelligence" comes in. Also when I started collecting my bonsai trees a few years ago I did not know that the pot was more like a dish or that I had to wire my tree to form the shape, I did research of course and went to a Bonsai society meeting before I bought my first tree. I had to gain knowledge before I could get into my new hobby. Because I got so into Bonsai, I research this subject every time I have questions or ideas...because of this I now know alittle about Asian Style landscaping and the history of these things play a huge roll in the decisions I make with my plants, Example: I would not put a Japanese maple in a Chinese pot - I think that would show inexperience and somewhat disrespectfull to the art. So there is deffintly both intelligence and creativeness with bonsai.
For me, This is more than an art form, even though that's why I like it so much but it's also a scientific experience for me. I've always tried to find the logical explanation for things and think practicly about things. I come from a long line of farmers and gardeners and as a job I do gardening (not landscaping). I didn't graduate High School but I have enough "intelligence" to do my job well which touches on my hobby. Knowing about plants in general has really helped me.
I think this person wanted to say alot but either didn't know how or just lost the train of thought. I deffinetly think it's both intelligence and creativeness that makes a bonsai what it is. There are people out there (I've met) that know so much about they're trees in speciffic that they can tell you the nutrients that tree needs, why, and when.
If there wasn't a level of intelligence needed then how would you know when to fertlize or prune?
If there wasn't a level of creativeness needed then how would you know how to shape you'r tree and the pot that should be used?
Just something to think about
Thanks,
Gardener