The Roots of Progress

Why did it take so long to invent X?

Some inventions obviously depended on a breakthrough discovery, such as a new scientific theory, and were developed not too long after that theory. The telegraph, for instance, was invented very soon after the physical theory of electromagnetism was worked out. Other inventions were dreamed up long before the underlying technologies were possible, such as da Vinci’s helicopter or Babbage’s computer—ideas ahead of their time.

But some inventions seem to have come along much later than they were possible, raising the question: why wasn’t this invented much earlier? Alex Tabarrok calls these “ideas behind their time”.

This page collects analyses and hypotheses about such ideas. (Inclusion here does not imply endorsement of the analysis.)

Specific inventions

Open questions

Examples that could use more thorough/convincing analyses:

General thoughts


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