I don't quite follow. Isn't buying shares de facto "investing" ?

(You may have a point on the shorting of shares, but that serves a purpose too; to devalue overpriced assets)

I think he's making a distinction between "classical" investment and Wall Street-style investment (for lack of better terms). There's an ideal that an investor puts money into a business that he thinks has potential to succeed (e.g. VC funding), and reaps his rewards through the success of the business.

Then there are others who invest purely as stock price speculation, and is generally disinterested in the actual goings-on of the business beyond what is likely to impact short-term stock price.

I see what you're saying, but I don't perceive a meaningful difference between those two classes beyond, perhaps, what's in the investor's head.

In both cases you're investing money in a company because you think the value of that company is likely to rise in the future. And in both cases the company benefits from that investment.

I agree that many investors are too focused on the short-term... but if they think they can make more money by selling a stock and reinvesting elsewhere rather than holding onto it for years, can you really blame them? The whole point of investing is to make a return on your principal.

A company sells 1000 shares. All get sold. Any further rrselling of those shares aka the stock market does not benefit the company.

At least not directly. E.g. it's easier to sell more stock or sell a bond with a healthy stock price.

Viewed another way, the stock _is_ the company.