The Dow JonesĀ has gained more than 120% from its lows four years ago.

But can we really call it a bull market? The big gains over the last four years came after a torrential loss in 2008. And the previous market highs in 2007 got us barely above the old highs set in 2000, particularly for the S&P 500 (SNPINDEX:^GSPC).

Whether or not we're now in a new bull market, or just a temporary pop in the middle of a longer bear market, remains to be answered. Alas, it can only be answered years from now, with the benefit of hindsight.

Still, everyone's got an opinion. Earlier this month, I asked Liz Ann Sonders, chief market strategist of Charles Schwab, what she thought. Have a look (transcript follows):

Sonders: If somebody sort of put a gun to my head and said, is the bull market we're enjoying right now for the past four-plus years, is it just a cyclical bull within a secular bear market or what began in March of 09, is it a new secular bull market? I'm biased toward the latter. I think this is a new secular bull market. I think ultimately knowing the answer to that, which we will only know in hindsight, would make a huge difference in terms of thinking about how one should position portfolios and approach things like diversification and rebalancing.

You can have some pretty nasty corrections still within secular bull markets. The perfect example would be the crash of 87, came within a secular bull market, so it's important to explain to investors what is meant by those things, but clearly a secular bull market tends to be longer lasting, obviously. The slope of the line is up versus just a cyclical bull, so you've got more duration, you've got more opportunity, but if I could definitively know the answer to that question right now, I think this would be much easier for someone in my position of trying to give advice to investors. Again, I have a bias, but I certainly am not out there saying, I'm absolutely convinced that this is a new secular bull market.

Fool contributor Morgan Housel has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. 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.