There are compelling reasons for why the stock market has not yet peaked, Morgan Stanley Chief U.S. Equity Strategist Adam Parker said Tuesday.

"I'm convinced that there's two things that cause the top of the cycle, two things only," he said "One, hubris, froth, some sort of excess, capital spending, inventory, hiring, M&A, new corporate headquarters that look fancy, whatever.

"And the other is debt. And the key right now is while there's lots of debt, none of it's due right for two or three years, so nobody can really go bankrupt, very few companies can go bankrupt, so I know I'm not at the top of cycle with more confidence than I did a year ago."

(Read more: Is Apple stock really a no-brainer?)

On CNBC's "Fast Money," Parker said that business leaders weren't exactly in freewheeling mode.

"The perversity of all this quantitative easing globally is CEOs aren't that confident," he said. "What does that mean? They're not spending money and putting costs in place that could collapse their earnings."

Parker also said that the government shutdown wasn't the end-all for stocks.

(Read more: Shutdown could trigger 'Fed flare': Brian Kelly)

"It's probably only going to hurt the GDP by a small amount," he said, adding that the previous government shutdowns were followed by rallies in the stock market.

"I think the bigger issue is: What could cause the bear case in earnings?"

Parker said that he didn't think that was likely.

"I don't think that's really a realistic scenario," he said, noting that earnings around the world were improving.

(Read more: Get cautious on stocks: Strategist)

Parker's top sector pick was industrials, and his 12-month price target for the S&P 500 was 1,840.

— By CNBC's Bruno J. Navarro. Follow him on Twitter @Bruno_J_Navarro.

Trader disclosure: On Oct. 1, 2013, the following stocks and commodities mentioned or intended to be mentioned on CNBC's "Fast Money" were owned by the "Fast Money" traders: Jim Lebenthal is long AAPL; Jim Lebenthal is long BAC; Jim Lebenthal is long GS; Jim Lebenthal is long JPM; Jim Lebenthal is long WFC; Jim Lebenthal is long MS; Jim Lebenthal is long INTC; Jim Lebenthal is long WMT; Jim Lebenthal is long FB; Jim Lebenthal is long MRK; Jim Lebenthal is long F; Jim Lebenthal is long DIS; Jim Lebenthal is long CMCSA; Jim Lebenthal is long TWX; Jim Lebenthal is long CZR; Jim Lebenthal is long NLY; Jim Lebenthal is long BA; Brian Kelly is long treasury ; Brian Kelly is long gold; Brian Kelly is long natural gas; Dan Nathan is long AAPL; Dan Nathan is long NFLX; Dan Nathan is long TSLA; Dan Nathan is long GM; Dan Nathan is long MSFT; Dan Nathan is long WFM; Dan Nathan is long ZNGA; Dan Nathan is long XCO; Dan Nathan is long calls VIX short puts VIX ; Dan Nathan is long calls XOM; Guy Adami is long C; Guy Adami is long GS; Guy Adami is long INTC; Guy Adami is long MSFT; Guy Adami is long AGU; Guy Adami is long NUE; Guy Adami is long BTU; Guy Adami's wife, Linda Snow, works at Merck; Yaron Werber is long GILD; Yaron Werber is long CELG.