Morde­cai M. Kaplan: Rest­less Soul by Jen­na Weiss­man Joselit is an illu­mi­nat­ing account of one of the twen­ti­eth cen­tu­ry’s most impor­tant and tena­cious Jew­ish lead­ers. Metic­u­lous­ly researched, the book relies heav­i­ly on Kaplan’s own writ­ings — specif­i­cal­ly draw­ing from note cards in long for­got­ten box­es and Kaplan’s many jour­nals. With such close atten­tion paid to Kaplan’s inner life, Joselit is able to write a biog­ra­phy that is both infor­ma­tive and human­iz­ing, simul­ta­ne­ous­ly fram­ing, explain­ing, and com­pli­cat­ing Kaplan’s life. 

Morde­cai Kaplan lived 102 years and remained prodi­gious at every stage of his life. As such, Joselit had to choose which aspects of Kaplan to high­light in her work. Where many oth­er works choose to empha­size Kaplan’s the­ol­o­gy, Joselit instead focus­es more of her ener­gy on Kaplan as a builder of insti­tu­tions. Whether read­ing about the Jew­ish Cen­ter in New York, the Soci­ety for the Advance­ment of Judaism (SAJ) on the Upper West Side, or the cre­ation of the Amer­i­can Jew­ish Uni­ver­si­ty, one emerges from their read­ing under­stand­ing the tri­als and tribu­la­tions of found­ing and run­ning such a diver­si­ty of orga­ni­za­tions. Kaplan may have been a bril­liant writer and an icon­o­clas­tic thinker, but it was his work fos­ter­ing com­mu­ni­ty in syn­a­gogues, schools, and non­prof­its that proved the most con­se­quen­tial for Amer­i­can Judaism. 

From her close read­ings of Kaplan’s writ­ings, Joselit is able to give us insights into Kaplan’s inter­per­son­al strug­gles. Kaplan was not an easy per­son to work with — he had an unflap­pable vision and opin­ions he was not afraid to share. That often meant that he was not at home in any space, whether Ortho­doxy, where he got his start, Con­ser­v­a­tive Judaism, where he spent most of his career, or even Recon­struc­tion­ist Judaism, which he found­ed. His dis­agree­ments with his Recon­struc­tion­ist dis­ci­ples proved espe­cial­ly painful for him. As he aged, Kaplan had to watch many of his mentees take his move­ment in a dif­fer­ent direc­tion than he would have envi­sioned for it. 

In addi­tion to explor­ing the insti­tu­tions and writ­ings that Kaplan con­tributed to, Morde­cai M. Kaplan: Rest­less Soul pays close atten­tion to Kaplan, the man. We learn about the twice dai­ly walks Kaplan took in order to pre­serve his health, how he mourned his beloved wife Lena and found love again with Riv­ka Rei­gler, and what he was read­ing at any giv­en peri­od of his life. The book also expert­ly explores the para­dox­es of Kaplan’s life; for instance, Joselit asks how a man for whom pas­sion and deep con­nec­tion to Judaism is para­mount could cre­ate a move­ment and write trea­tis­es that were often crit­i­cized for being over­ly cere­bral. Or how a per­son who was the charis­mat­ic cen­ter of the insti­tu­tions he found­ed some­times avoid­ed the lime­light. Or how Kaplan’s most endur­ing intel­lec­tu­al lega­cy was teach­ing the Jew­ish com­mu­ni­ty about the pow­er of peo­ple­hood, yet he often found him­self at odds with the exact peo­ple he sur­round­ed him­self with.

In sum, Morde­cai M. Kaplan: Rest­less Soul is a well-researched, thought­ful, and deeply human explo­ration of one of the most con­se­quen­tial fig­ures in recent Jew­ish history.