= All You Need Is Lambda! =
This is mantra by honorable prof. Brian Harvey of UC Berkeley. It means that any computation could be defined using nothing but application of procedures (wich is formalized by [wiki:/FirstPrinciples/LambdaCalculus Lambda Calculus]).
[wiki:/Languages/Scheme Scheme] could be considered as an implementation of "Untyped" Lambda Calculus.
Just sing it - '''All You Need Is Lambda!'''
''Happy. Happy. Joy. Joy.''