What's more, there's evidence that the economy has begun an adjustment that will allow for a less-than-cataclysmic response to tougher times. As one of my Fast Company colleagues, senior editor George Anders, recently pointed out in a debate with Mandel on ABCnews.com, the new economy has demonstrated a capacity to fix its problems faster, and with less anguish, than the steel industry or the auto industry ever did.

But you don't have to join Mandel's bandwagon of doom in order to appreciate the power and the value of his book. For anyone who wants to understand how the first round of the new economy took shape and how to wrestle with the macroeconomic challenges facing us in the second round, a great place to start is The Coming Internet Depression.

Let Bygones Be Bygones

If The Coming Internet Depression offers grim arguments and hard-core analysis, The New Gilded Age plays more like a greatest-hits soundtrack for the new economy. The New Yorker, a magazine born just before the Great Depression, has done an amazing job of bringing its signature journalism to the zeitgeist of the Internet age. This collection of articles offers serious profiles of big-time moguls and thinkers. It also profiles some of the oddball characters that only the Internet boom could have created. My favorite: Larissa MacFarquhar's piece on Jason McCabe Calacanis, founder of the Silicon Alley Reporter, a young kid who seems willing to say and do anything for attention. (It is fitting testimony to the temporary insanity of the Internet age that Calacanis's profile appears before those of Bill Gates, Alan Greenspan, and Martha Stewart.)

The overall effect of reading these articles is an appreciation of just how drunk we were during the dotcom daze -- and how hard it's going to be to get rid of the hangover. What's still true about the Internet economy when it comes to how you build great companies or how you create value? And what was never true about the Internet economy? Which "new rules" of competition do we have to discard as being misguided, naive, or flat-out wrong? Those are some of the questions that any reader of these New Yorker pieces will be left to ponder.

To me, the most compelling article in this compelling collection is John Cassidy's profile of Mary Meeker, the Morgan Stanley Dean Witter analyst who was made famous (and rich) by the Internet boom. The piece, called "The Woman in the Bubble," was published in April 1999 -- about a year before the bubble burst. But even back then, Cassidy paints a portrait of Meeker as an evangelist who was getting uncomfortable with her religion, as a true believer who was beginning to have some doubts about her faith. Early in the piece, Cassidy describes the IPO (led by Meeker) for priceline.com -- a company that had been operating for less than a year and that had achieved a market value of $11 billion. And yet, even at such a triumphant moment, Meeker tells Cassidy, "I think we will have a big correction in Internet stocks sometime this year."

By the end of the profile, Meeker's disgust with Internet excess is palpable. She talks to Cassidy about some of her meetings with startup-company CEOs: "They were unbelievably arrogant about how successful they were going to be, and they were unbelievably arrogant about the valuations they wanted to achieve on their I.P.O. I was just pissed. I was like, 'Come on, guys.' " Meeker says that she sensed a huge gulf between first-generation Internet entrepreneurs and those leading the second wave. "The first generation was like, 'Hey, isn't this great! I'm a billionaire! Well that's kind of embarrassing. What am I going to do with all this stuff?' The next generation is saying, 'Well if he's a billionaire, then I've got to be a billionaire.' With every I.P.O., the envelope is pushed a little further. At some point, you have to scream 'uncle.' "

The anguish that you heard last spring on Wall Street was the sound of the new economy screaming uncle. The issue before us now is what comes next. Can we keep what's been so powerful about Internet-inspired innovation, and discard what's been so dubious? Can we have change-the-world creativity without out-of-this-world stock markets? Can we have visionary leadership without ego-driven delusions of grandeur? Those are the questions that will occupy us for the next five years. Far from depressing, the search for answers should be quite a ride.

Sidebar: Cheat Sheet

Too depressed about the end of the boom to read these books? A few highlights from The Coming Internet Depression.

Not All Booms Are Created Equal. "Between the middle of 1995 and the middle of 2000, about 45% of the rise in the market value of the S&P 500 came from the tech sector. Just four companies -- Intel, Microsoft, Cisco, and America Online -- were responsible for an increase of more than $1 trillion in market value.... "