NEW YORK (TheStreet) --The market collapse yesterday raises some interesting questions about who the markets serve.

Are these stock gyrations really reflecting the informed outlooks of smart investors who doubt the fundamentals and future earnings potential of stocks of all stripes, including Caterpillar ( CAT - Get Report), Boeing ( BA - Get Report), and Pfizer ( PFE - Get Report)?

Or are we seeing the consequences of the rapid expansion of computerized algorithmic trading, which by some estimates account for more than half of all equity trades.

Over on RealMoney Silver, Doug Kass observes that "high-frequency-trading funds are very active and have taken the role as the dominant investor in the U.S. stock market. The market's spastic action reflects, in part, the disproportionate role of high-frequency-trading funds on the market over the past few weeks."

So we can blame the machines.

Machines don't understand the responsibilities of ownership. They obviously don't care about the fundamentals behind the numbers or understand the power of responsible and responsive corporate leadership.

Beyond that, what's wrong with high-tech trading? In my opinion, it's too fast and too stupid. I like to think humans are smart enough to avoid a massive selloff like we had yesterday, when there was no particular news or event that merited such a drop.

Jim McTague, the Washington editor over at Barron's, has even harsher words for computerized, high-frequency trading that are clearly expressed in the title of his new book: Crapshoot Investing: How Tech-Savvy Traders and Clueless Regulators Turned the Stock Market into a Casino.

McTague says a single day of high-frequency trading is like 30 years in human trading terms, and he notes that as a result of these computer trading systems 2% of market participants generate 70% of equities volume.

Life's too short to move that fast.

Besides, equity markets are not supposed to be computerized gambling parlors where the best programmers win. They are supposed to be a place for investors to take an ownership interest in a company and share in the risks and rewards of corporate activity.

Do investors really think Caterpillar is a losing proposition deserving an 8% decline over the past five days? Or is that just the machines doing all the thinking for us?

With all the talk about today's jobs report, does it mean nothing that Caterpillar recently announced a $50 million expansion in North Dakota that will create 250 jobs? OK, maybe that's minor, so how about Caterpillar raising its outlook after second-quarter profit topped $1 billion as sales climbed 37%?

What about Boeing then - do people see no hope for a company that recently landed massive order from American Airlines ( AMR - Get Report). No love for the optimism of American Airlines either, it seems, or the boon to General Electric ( GE - Get Report), whose new, fuel-efficient engines will power many of the new planes.

Too industrial? Well then let's look at Pfizer, which is down 9% in the past five days. Just this week the drugmaker reported a 5% increase in earnings, beating expectations, and went on to affirm its forecast for the full year. That sounds ominous! Worse still, Pfizer is looking to create value for investors with plans to spinoff or sell its animal health and nutrition business, which would provide cash for a potential share buyback, dividend or to reinvest in its core drug business.

Even old-school media businesses like CBS ( CBS - Get Report) are reporting solid results, with the network doubling second-quarter profit as it pushed into digital distribution through content deals with Netflix ( NFLX) and Amazon ( AMZN). That can't be good at all.

I can see why the machines might object to CBS going digital, but stocks aren't for machines.

Stocks are for people.

--Written by Glenn Hall in New York. Follow Glenn on Twitter @ glennhall.

Disclosure: TheStreet's editorial policy prohibits staff editors and reporters from holding positions in any individual stocks.