1. It’s treatable by various antidepressants.

2. It’s exacerbated during the winter months.

3. It’s recognizably expressed in the music of Buddy Guy.

4. You’ve spent hundreds of dollars on books that ask you to express it through a series of charts and graphs and yet you find these visual representations lacking.

5. You want to laugh like children and live like lovers, but instead you find it hard to concentrate and complete previously easy tasks.

6. It’s accompanied by the realization that sad songs say so much.