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Your search for Who said things should be as simple as possible but no simpler than that returned the following results:

with a caveat by Albert Einstein

On the other hand, we can temper Thoreau's advice with a caveat by Albert Einstein: "Everything should be made as simple as possible, but not simpler."

In the words of Albert Einstein

In the words of Albert Einstein, “Everything should be made as simple as possible - but not simpler.”

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attributed to Albert Einstein

We are inspired by the quote attributed to Albert Einstein that ' things should be made as simple as possible, but not simpler'.

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Albert Einstein, who was a pretty smart guy

Albert Einstein, who was a pretty smart guy, once said, 'Make everything as simple as possible, but no simpler.'

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Even that regularly quoted genius , Albert Einstein,

Even that regularly quoted genius, Albert Einstein, said, “Make things as simple as possible, but not simpler”.

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Albert Einstein (one of the greatest minds in history)

Albert Einstein (one of the greatest minds in history) caution that we should, “Make things as simple as possible, but not any simpler.”

Albert Einstein who said that things should be as simple as possible — but no simpler

It was Albert Einstein who said that things should be as simple as possible — but no simpler.

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Albert Einstein, who said "Everything should be made as simple as possible, but no simpler"

We follow Albert Einstein, who said "Everything should be made as simple as possible, but no simpler".

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Albert Einstein, who said that we should make things as simple as possible, but no simpler

This principle is best illustrated by Albert Einstein, who said that we should make things as simple as possible, but no simpler.

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Even Einstein

Even Einstein said, “make things as simple as possible but no simpler.”