Leech with students. . . the journal Algebra Universalis, established the current definition of the concept, and he continues to be a major contributor to the study of lattices and idempotents. David Hunter observes that Jonathan has "certainly been the most prolific researcher in the department during his thirty years. His way of teaching and talking about mathematics with students gives them a real taste of the way a mathematician thinks."

After graduating from the University of Hawai'i, Jonathan completed a theology degree at Dallas Seminary and then earned his Ph.D. in mathematics from UCLA. He has supervised several European Ph.D. students, including Karin Cvetko-Vah, who got her degree from the University of Ljubljana in Slovenia. This summer Jonathan was able to meet with Karin and her own Ph.D. student—Joao Pita da Costa, from Portugal. The photo of the three of them displays three generations of mathematicians.

Jonathan's love of travel was something that he shared with his wife Pat, who passed away in the spring of 2012. Not too long after Jonathan arrived at Westmont, he met Pat when she was an administrative assistant in the dean's office. As the story goes, she once helped him figure out a fax machine. Over the next couple decades they saw the world together and opened their home to students.

A number of those students, now alums, continue to seek out Jonathan's company. "In the years ahead," promises Patti Hunter, "I'm sure we can expect to find Jonathan sitting in a coffee shop downtown, proving theorems or sharing a meal with a former student."