Is science running out of important questions?

On vacation last week, over a car trip between Sienna and Florence, my brother and I had a great discussion/debate: is science running out of important questions to ask?

Here's the gist of Sam's argument:

Science has already mapped most of the easily observed phenomena in the universe. We can explain why the sky is blue, why the sun rises in the east and sets in the west, why things fall, etc. Although we will never run out of questions to ask using the scientific method,the big ones are already taken. What's left is filling in details.

My counterargument:

The scientific method is a hydra: every question we answer raises several more. In hindsight, the scientific accomplishments of the past look easy, but it was no mean feat for Leonardo to work out the details of portraying perspective and distance, or for Galileo to figure out that gravity is constant once density is taken into account. (We were sightseeing in Italy for this talk.)

Not only are we not running out of questions, we have more important questions before us today than ever before. For example:

• Why does every language have a grammar (linguistics)?
• Why do wars happen (political science)?
• Why do recessions happen (economics)?
• Where does consciousness come from (psychology and neurobiology)?
• Here are 25 more from the NYTimes
  

I'm still not fully persuaded either way. Both arguments seem at least partly true, and I haven't been able to restate them in terms where they can be adjudicated.