Art Cashin said it appears the stock market's recent strength "is more than just a reflex rebound" and could have legs but it's still too soon to know for sure.
Cashin, UBS' director of floor operations at the NYSE, told CNBC's Dominic Chu around midday that he's not seeing the caution flags that could signal the beginning of a broader move lower.
"This is somebody who had an accident, tripped and fell, and now they're getting up and saying, 'Wait a minute. I think I'm all right.' And we'll see."
"Now, does that mean they are all right? No, not yet, but we're in that check out phase and people are going to see how they're going."
Cashin thinks Friday could be "critical" as we see if the situation in Ukraine worsens and financials start reporting earnings.
Even so, "It does look like people may want to start tiptoeing into earnings season later in the week."
—By CNBC's Alex Crippen. Follow him on Twitter