[1] Keller was a draftsman, painter, sculptor, and teacher who instructed students in the visual arts for forty years, most notably in figure drawing and the artistic application of human anatomy.
He is credited with explaining that "drawing offers a unique record of an encounter with a culture, of experience transformed from fleeting moment to lasting resonance.
Additionally, Keller studied in Florence, Italy, with Nera Simi, and anatomy under David Rubins at the Herron School of Art in Indianapolis, Indiana.
[4] A portrait, landscape and still life painter, Keller was in his later years engaged in a series of large charcoal drawings of draped figures inspired by his travels to the Middle East.
Keller believed that "for some years the fine art of draftsmanship has suffered some eclipse because learning the craft of figure drawing has been only casually addressed and even discredited by some.