The cost of innovation has risen, and productivity has suffered

WERE there far fewer undiscovered ideas out there than in our more primitive past, how would people know? This is not an idle question; decoding the mysteries of nature, from atmospheric pressure to electricity to DNA, allowed people to bend the natural world to their will, and to grow richer in the process. A dwindling stock of discoverable insights would mean correspondingly less scope for progress in the future—a dismal prospect. And some signs suggest that the well of our imagination has run dry. Though ever more researchers are digging for insights, according to new research, the flow of new ideas is flagging. But that uncovering new ideas is a struggle does not mean that humanity is near the limits of its understanding.

The development of new ideas—meaning scientific truths or clever inventions—allows economies to grow richer year after year. Adding more workers or machinery to an economy boosts GDP, but only for a while. Applying ever more men with hoes to the cultivation of a field will generate diminishing returns in terms of crop yields, for instance; wringing more from the soil eventually requires the use of better seed-stock or fertiliser. Unless humanity finds new ways to do more with the same amount of labour and capital, growth in incomes peters out to nothing.