Both Pepper (1891-1972) and Churchman (1913-2004) share a lineage back to [William James (1842-1910)](https://iep.utm.edu/james-o/) through [Ralph Barton Perry (1876-1957)](https://www.giffordlectures.org/lecturers/ralph-barton-perry) and [Edgar A. Singer (1873-1954)](https://en.wikipedia.org/wiki/Edgar_A._Singer_Jr.).
digraph PepperChurchman { // Global setup rankdir = BT // Node list {rank=same ucb1 cwc} {rank=same ucba upp} {rank=same ucb2 ucbb} {rank=same ucbp} mc [shape=box color="green" label="Metaphysical\nClub\nCambridge, MA\n1872"] csp [shape=oval color="blue" penwidth=3 label="Charles\nSander\nPeirce\n1839-1914\nFather of\nPragmatism"] wj [shape=oval color="blue" penwidth=3 label="William\nJames\n1842-1910\nFather of\nAmerican\npsychology"] rbp [shape=oval color="blue" penwidth=3 label="Ralph\nBarton\nPerry\n1876-1957"] eas [shape=oval color="blue" penwidth=3 label="Edgar A.\nSinger\nJr.\n1873-1954"] scp [shape=oval color="blue" penwidth=3 label="Stephen \nC.\nPepper\n1891-1972"] ucb1 [shape=oval color="blue" penwidth=3 label="Professor of\nPhilosophy\nU. California\nBerkeley\n1919-1938"] ucba [shape=oval color="blue" penwidth=3 label="Chair of\nArt\nDepartment\nU. California\nBerkeley\n1938-1952"] ucb2 [shape=oval color="blue" penwidth=3 label="Chair of\nPhilosophy\nDepartment\nU. California\nBerkeley\n1953-1972"] cwc [shape=oval color="blue" penwidth=3 label="C.\nWest\nChurchman\n1913-2004"] upp [shape=oval color="blue" penwidth=3 label="Chair,\nPhilosophy\nDepartment\nU. Pennsylvania\n1945-1948"] ucbb [shape=oval color="blue" penwidth=3 label="Professor,\nBusiness\nAdministration\nU. California\nBerkeley\n1958-1981"] ucbp [shape=oval color="blue" penwidth=3 label="Professor,\nEmeritus\nPeace &\nConflict Studies\nU. California\nBerkeley\n1981-1994"] // Adding edges mc -> csp [dir=both arrowtail="onormal" arrowhead="onormal" arrowsize="0.8" label="affects"] mc -> wj [dir=both arrowtail="onormal" arrowhead="onormal" arrowsize="0.8" label="affects"] wj -> eas [arrowhead="curve" arrowsize="1.5" label="is\nexhibited\nby"] wj -> rbp [arrowhead="curve" arrowsize="1.5" label="is\nexhibited\nby"] rbp -> scp [arrowhead="curve" arrowsize="1.5" label="is\nexhibited\nby"] scp -> ucb1 [arrowhead="curve" arrowsize="1.5" label="is\nexhibited\nby"] ucb1 -> ucba [arrowhead="vee" label="leads\nto"] ucba -> ucb2 [arrowhead="vee" label="leads\nto"] eas -> cwc [arrowhead="curve" arrowsize="1.5" label="is\nexhibited\nby"] cwc -> upp [arrowhead="vee" label="leads\nto"] upp -> ucbb [arrowhead="vee" label="leads\nto"] ucbb -> ucbp [arrowhead="vee" label="leads\nto"] }
There's overlap in the branches of intellectual development in World Hypotheses and Inquiring Systems.