Then again, maybe the world is full of zombie-like humans and gray, gray weather. After all, our speaker does hail from England. And the UK isn't exactly a tropical paradise. You'd think that our speaker would want to buy a one-way ticket to Aruba, right? Instead, he seems to obsess over the barren British countryside.
Things go from dull and depressing to outright dismal. No life seems to stir. Anywhere.
...Until, that is, our speaker hears the most unexpected sound: a bird singing. The little thing isn't in the best of shape. It's been beaten badly by the weather, and it seems as old and death-bound as the year itself. That doesn't stop it from belting its heart out, though. It's bound and determined to share every last ounce of joy in its soul.
Why be joyful when the world is so crummy? Well, that's a good question. In fact, that's exactly the question that our speaker asks himself. He can't figure out why in the world anything – let alone a bird – would waste its last breath in a song that no one will hear. Unfortunately, our feathered friend doesn't give him any answers. (What do you think this is, Disney? Birds don't talk, folks. Which makes it a bit tricky for out speaker to get any answers.)
Strangely enough, our speaker doesn't even try to figure it out. He's content to know that something out there sees a reason to exist and to be joyful – even if he can't comprehend the reasons himself.