It was a historic day on Wall Street as the S&P 500 index on Monday passed the 2,000 level for the first time. Yet veteran trader Art Cashin was largely unimpressed.
Though Cashin, director of floor operations at the NYSE for UBS, acknowledged S&P 2,000 is an "achievement," he found several reasons to pour cold water on the celebrations.
"It was more psychological than technical," he said on "Squawk on the Street." "You know, if it was a point that was technically important, the people who are short—and there are more than a few people short—would have said, 'Oh, my God. That's it. Let me capitulate and cover my short there.' "
Cashin also noted that volume is incredibly low, meaning relatively few shares are exchanging hands. If volume were high, S&P 2,000 might mean more, he said.
"Over the decades, I have been taught volume equals validity," Cashin said. "Just as you wouldn't want the president of the United States picked by eight people, you want to see some real volume to get validity in there."
Cashin clarified that he doesn't think S&P 2,000 is meaningless, though.
"I mean, numbers are numbers. We've made it to 2,000," he said. "But the fact that there was no short-covering or instant follow-through just makes it an item of note."
—By CNBC's Drew Sandholm.