CREATE TABLE table_16607 ("Date" TEXT, "Founder" TEXT, "Extroversion Scales" TEXT, "People-task orientation scale" TEXT, "Introverted ,  Task-Oriented" TEXT, "Extroverted ,  Task-Oriented" TEXT, "Extroverted ,  Relationship-Oriented" TEXT, "Introverted ,  Relationship Oriented" TEXT, "Moderate" TEXT)

who is the founder where date is c. 1900
SELECT "Founder" FROM table_16607 WHERE "Date" = 'c. 1900'
SELECT "Founder" FROM "table_16607" WHERE "Date" = 'c. 1900'