Out of curiosity, what's the alternative to if/else? Assuming polymorphism wasn't around in the 50's, did people express the idea of conditional execution based

Out of curiosity, what's the alternative to if/else? Assuming polymorphism wasn't around in the 50's, did people express the idea of conditional execution based on the result of evaluating some expression using and/or? Does this mean that lazy evaluation was around before conditionals?