So, I have heard a fair number of people make a distinction between gambling and investing (ie. gambling is wrong, investing is at least permissible). I find it hard to find a clear distinction between the two. Here are a couple distinctions you might try to make, and what I think is wrong with them.
1. Gambling is an attempt to 'get rich quick'.
Well, this might be so for most gamblers, but there is nothing about gambling that makes it about getting rich quick. After all, one could make long term bets (ie. betting on what will happen in 2020) or bets that will not be payed out for a while. There does not appear to be anything essential to gambling about getting rich quick. It is hard to imagine that those who oppose gambling oppose only the get rich quick kinds of gambling, and would have no problem with a bet that gets paid off far into the future. The distinction must lie elsewhere.
2. Gambling is associated with a shady lifestyle.
Whether this is so, it is irrelevant to the distinction at hand unless it can be shown that the shady lifestyle is shady in virtue of gambling. In other words, the association may point to a problem, but it is not itself the problem. In addition, the lifestyle associated with investing is not much better. Both worlds are full of greed and ego and have stories of people who lost it all (think Great Depression). It is difficult to see how the two can be distinguished in this way.
3. Gambling relies on chance.
This is perhaps the best shot at a clear distinction, but it too has problems. First of all, investing also relies on chance. Chance events can greatly affect the value of a company's stocks (ie. a plane crash hurts that airline). So, chance has a great deal to do with one's investments. One might reply that events like airplane crashes, earthquakes and such are not chance events, but then it is hard to see how the roll of a dice is a chance event either. Even if it is granted that gambling relies on chance in a way that investing does not, it remains to be seen how such a reliance makes gambling a worse activity. Many other activities rely on chance that we do not have a problem with.
All of this is not to encourage or discourage gambling or investing, but simply an ongoing failure to find a suitable distinction between the two.
Next up: searching for a distinction between saving money and hoarding money. They sound so different, but are they?