Two years ago, the inversion of the yield curve—shorter-dated Treasurys yielding more than longer-dated bonds—was taken by investors as a surefire sign of recession. Now Wall Street worriers have a new concern: The yield curve is back to normal, a surefire sign of recession.

It might seem odd, but both yield-curve moves are indeed good signs of recession, though not foolproof ones. What really matters is why Treasurys move as they do, and in this case it comes down to the Federal Reserve.

The Fed is expected to embark on a series of interest-rate cuts starting next week, which is why short-dated bond yields have fallen fast, uninverting the yield curve when measured as the 10-year minus two-year yield. If those cuts are purely because inflation has dropped back close to target, that is the ideal of a soft landing for the economy, and absolutely not a sign of imminent recession.

But for most of modern history, deep rate cuts by the Fed have been a sign that the country is about to plunge into recession, or is already in one that economists missed.