Is Pujols the greatest hitter of all time?

I asked my colleague Jim Caple a simple question: "Who is on your short list of the greatest hitters of all time?"

He reeled off the names: Pujols, Bonds, Ruth, Williams ... Mays, Hornsby, Cobb (a little reluctantly on that one). We could include a few others, of course -- Gehrig, Aaron, Musial.

Anyway, maybe we'll do a more thorough examination of this question in the offseason. This is just a quick primer as we sit here waiting for the start of Game 4.

Here are the all-time leaders in FanGraphs' wRC+, which compares a hitter's runs created to an average player and is park- and league-adjusted, so a batter with a 150 wRC+ created 50 percent more runs than average:

1. Babe Ruth, 197

2. Ted Williams, 189

3. Barry Bonds, 175

4. Lou Gehrig, 174

5. Rogers Hornsby, 171

6. Ty Cobb, 171

7. Mickey Mantle, 171

8. Albert Pujols, 167

Here is the case against each of those eight, plus Willie Mays:

Babe Ruth

Case against: The advanced statistics don't factor in a timeline adjustment -- or what can be called the evolutionary improvement in the game. Overall, the players in Ruth's era were not as good, not as big and strong as today, the equipment wasn't as good, the fields not as good. This made it easier for a great player to excel above a league-average type of player. Put it this way: Ruth did not have to face guys like Alexi Ogando throwing 97-mph fastballs and 89-mph sliders. You think Ruth would be able to get the 40-ounce bat he used in 1927 around on a 100-mph Justin Verlander heater?

Ted Williams

Case against: The era he played in was perfect for him, a time when pitchers walked more hitters than now, amplifying Williams' skill-set -- patience the plate -- even more. Only hit 40 home runs once. While wRC+ accounts for Fenway being a great hitter's park, it perhaps doesn't fully factor in the advantage it gave Williams, who hit .361 there, .328 on the road. Integration didn't come until the second half of his career, and even then the AL lagged behind the NL.

Barry Bonds

Case against: Bonds through the 1999 season: .288/.409/.559; Bonds from 2000 (when he turned 36 during the season) to the end of his career: .322/.517/.724.

Lou Gehrig

Case against: Played in the 1920s and 1930s, the best offensive era in major league history. Played before integration. Since he got sick, his last season came when he was 35, so he missed the decline phase of his career, which would have lowered his career wRC+ number (although boosting his overall numbers).

Rogers Hornsby

Case against: Fabulous peak, but last great season came when he was just 33. Same arguments here as Ruth and Gehrig; without a timeline adjustment it was easier to statistically excel over an average player. Here's another example about the quality of play issue: In the 1920s National League, when Hornsby dominated, the strikeout rate never topped 3.0 per nine innings. Are we to assume the hitters were all just awesome back then? Or is it possible pitchers just didn't throw as hard, and thus it was easier to put the ball in play?

Ty Cobb

Case against: Talk about a different era. Fielders used gloves barely bigger than their hands when he played. He hit with a split-handed grip, which I'm not sure would fly against 97-mph fastballs on a regular basis. H&B factory records list his bat sizes in 1920 as 36 to 38 ounces, and 37 to 40 ounces in 1921-22. All this suggests a batting style more like a guy slapping the ball in play, as opposed to trying to drive the ball on a regular basis. (I'm not exactly saying Ichiro here; more like a slightly more powerful version of Tony Gwynn.) Could he have hit for power in a different era?

Mickey Mantle

Case against: Short career, too many injuries. Never played 150 games in a season after turning 30.

Albert Pujols

Case against: Has yet to enter decline phase of his career, grounds into too many double plays, doesn't walk quite as much as OBP kings like Ruth, Williams, Bonds and Mantle. The big question here: Has he entered the decline phase of his career? The biggest red flag to me on his 2011 season is that his walk rate dropped significantly from previous seasons, as he was more aggressive at the plate (he swung at 44 percent of all pitches this season, compared to slightly less than 40 percent over the previous five seasons). This change of approach could signify a guy who recognized his bat speed has started to slow slightly and thus swung more often early in the count. Or it could simply be a situation of him getting more pitches to hit with Lance Berkman and Matt Holliday hitting behind him.

Willie Mays

Case against: Career on-base percentage is nearly 100 points below Ruth and Williams, lowering his career wRC+ to .157.