“It is clear that we have to pay more, it is the simple option, not always affordable, ("but simple," said in actual recording) but the ways to solve the problem are many.”

As quoted in Dynamic Work Simplification (1971) by W. Clements Zinck, p. 122

Ackoff (2007) as cited in: Stefan Stern (2009) "Fond farewell to a brilliant thinker". in: Financial Times, November 9, 2009.
2000s
Context: The only problems that have simple solutions are simple problems. The only managers that have simple problems have simple minds. Problems that arise in organisations are almost always the product of interactions of parts, never the action of a single part. Complex problems do not have simple solutions.

In some published transcripts or quotations of this speech a variant of this statement appears immediately before the quote by Churchill below, but was not said during Reagan's televised address on (27 October 1964). Though he did make variations of the speech elsewhere it is unclear exactly when and where he may have said used these precise words:
: They say the world has become too complex for simple answers. They are wrong. There are no easy answers, but there are simple answers. We must have the courage to do what we know is morally right.
Later variant: For many years now, you and I have been shushed like children and told there are no simple answers to the complex problems which are beyond our comprehension. Well, the truth is, there are simple answers, they just are not easy ones.
:* California Gubernatorial Inauguration Speech (5 January 1967) http://www.reagan.utexas.edu/archives/speeches/govspeech/01051967a.htm
1960s, A Time for Choosing (1964)

Source: Foucault's Pendulum

Dijkstra (1973) in personal communication to Donald Knuth, quoted in Knuth's "Structured Programming with go to Statements".
1970s

General Relativity Lecture 5, YouTube, published 30 October 2012 https://www.youtube.com/watch?v=quWN1V9jOf0 (quote at 1:21:46 of 1:39:06)

1930s, Address at the Democratic State Convention, Syracuse, New York (1936)
Context: Desperate in mood, angry at failure, cunning in purpose, individuals and groups are seeking to make Communism an issue in an election where Communism is not a controversy between the two major parties.
Here and now, once and for all, let us bury that red herring, and destroy that false issue. You are familiar with my background; you know my heritage; and you are familiar, especially in the State of New York, with my public service extending back over a quarter of a century. For nearly four years I have been President of the United States. A long record has been written. In that record, both in this State and in the national capital, you will find a simple, clear and consistent adherence not only to the letter, but to the spirit of the American form of government.