 After receiving his MA, Salmon decided to move to UCLA. Although he claimed to have taken that decision attracted by the warm Californian climate, his choice proved decisive, because there he encountered Hans Reichenbach, who supervised his Ph.D. dissertation on John Venn, and who exercised a dominant influence on all of his subsequent work. After obtaining his Ph.D. in 1950, Salmon held teaching positions at Washington State College; UCLA; Northwestern University, and Brown University.