Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

It was everything you'd expect the first Monday in October to be: excitement over the start of earnings season and relatively little in the way of economic data outside of the consumer credit report. Yup, unless you count the whole government shutdown entering its seventh full day and the debt-ceiling crisis screaming toward the S&P 500 (SNPINDEX:^GSPC) like an out-of-control locomotive, it was a normal day.

If there was any bright spot from today's trading it would be that the consumer credit report came in at $13.6 billion, a bit higher than economists had expected. Normally we don't like seeing consumers take on extra debts. However, as it is largely consumer-driven, the added debt for education loans and automobiles is a potentially great sign for the economy, as well as financial institutions, and could help GDP growth pick up.

Unfortunately, no resolution to the budget battle in Washington appears readily visible, making the prospect of a protracted government shutdown, and even a debt default, seem possible now.

With the political parties remaining quite divided, the S&P 500 dipped 14.38 points (-0.85%) to close at 1,676.12, its 10th drop in the past 13 sessions.

Leading all gainers within the S&P 500 today was robotic surgical device maker Intuitive Surgical (NASDAQ:ISRG) which added 4.7% following positive commentary from research firm William Blair. Specifically, analysts noted that if the safety of Intuitive's surgical system, da Vinci, turns out to be better than standard laparoscopic surgery, physicians will be even more encouraged to learn about and implement the company's products. In addition, William Blair believes that those with a six-month or longer time horizon will do well betting on Intuitive's shares to rebound. As for me, I'd like to think of things a bit beyond six months. I do see plenty to like about Intuitive's safety record and fully expect these near-term safety and efficacy fears to blow over. With a technological edge, amazing pricing power, and little to no competition, Intuitive Surgical in my opinion remains a potentially strong buy.

Also bucking the downward trend was hybrid real estate investment trust HCP (NYSE:HCP) which gained 2.1% despite a lack of company-specific news today. That wasn't the case on Friday, however, with shares dipping on the firing of CEO James Flaherty and the hiring of Lauralee Martin as his replacement. Any change at the top is cause for concern from shareholders that a company may "lose its way." Today's move appears to indicate abated fears for the company, as well as the fact that HCP is a smart defensive play in a down market. This REIT invests primarily in health-care facilities, which are only expected to command higher rents in the coming years given the Obamacare rollout. With a monstrous 5.4% yield, it appears investors are beginning to sniff out value in this stock.

Finally, defense contractors Northrop Grumman (NYSE:NOC) and Lockheed Martin (NYSE:LMT) both traded noticeably higher, with Northrop edging Lockheed 1.8% to 0.9%. The impetus behind the pop for both companies was the move by Defense Secretary Chuck Hagel to recall most civilian defense employees to the Pentagon despite the government shutdown. Ultimately, that could mean fewer layoffs for Northrop Grumman and Lockheed Martin, and less of a monkey wrench thrown into current projects. We still remain a long way from solving the government's ongoing budget issues, but this is certainly a start for these defense contractors.

Fool contributor Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

The Motley Fool owns shares of, and recommends Intuitive Surgical. It also owns shares of Lockheed Martin, and Northrop Grumman. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.