Walter declares at the outset that he is depressed, so an important question becomes, how accurate is the portrayal of depression?

Well, according to the DSM-IV - the therapist's long-standing playbook on mental disorders - depression has the following symptoms: loss of appetite, sleep, energy and pleasure (in doing pretty much anything), sense of sadness/tearfulness most of the time, psychomotor retardation or agitation (moving through your day either with restlessness or as if underwater), sense of worthlessness or excessive guilt, difficulties concentrating and, of course, the especially brutal kicker, suicidal thoughts and urges.

Now, it's helpful to know that people can experience a few definitive types of depression. Experience any five of these eight symptoms for at least two weeks and you've got a Major Depressive Disorder, and it's called "Major" for a reason. Experience any two of these eight symptoms (most of the time) for at least two years and you've got a more mild but chronic form of depression known as Dysthymic Disorder

These depressive disorders can be triggered by major life stressors or transitions like having a baby (Post-partum Depression) or even for no good reason at all (Seasonal Affective Disorder). Sometimes the depression can become so profound that it can make you catatonic; sometimes it comes in the form of melancholia, which is basically depression with a more soul-jerking loss of pleasure and, oddly enough, a tendency to be at its worst in the mornings.

"The Beaver" does not delve into the triggers or the history of Walter's depression but his presenting symptoms are crystal clear. He's got it bad - a Major Depressive Disorder, for sure, that we would likely qualify as "severe" (versus mild or moderate). He can barely get out of bed. He cannot get engaged in or enjoy any of his interactions with his perfectly healthy and happy family. Clearly he used to. He just can't anymore. Moreover, he doesn't seem to eat much, and he definitely doesn't sleep. Sleepwalking through life is a pretty good manifestation of low energy and psychomotor retardation. He wears his sense of worthlessness on his face like a neutral expression and if you didn't know that he was thinking suicidal thoughts then you could deduce it from his efforts at hanging himself (this happens in a rather jarring scene halfway through the first act).

So far, the movie has presented a picture of depression consistent with what depression is supposed to look like - high marks for diagnostic validity.

The essence of depression, which the film touches upon in the indirect, incomplete way that films tend to touch on real-world processes, is about voices, internal ones. Our life experience is driven by an internal dialogue. Some would argue that most of the time this voice is speaking to us in unconscious ways, but it absolutely underlies our feelings, thoughts and behaviors in every moment to moment experience, and it therefore shapes our life trajectory or story. A healthy, adaptive, non-depressed internal voice sounds something like the following: it fosters a view of one's self and others that is generally positive, compassionate and accepting. It problem-solves stresses, confronts anxiety-provoking situations, and finds ways of making meaning in the world and engaging with enthusiasm and singular focus in the tasks of daily living. It consistently pushes the mind to do what is healthy for the body, such as eating a balanced diet and exercising, which, in turn, allows the body to do the automatic things it needs to do like sleep.

The depressed internal voice is very different. It's much more intense and dark. It shapes a view of the self as worthless and pathetic. It views others in a pessimistic, embittered light. It worries about stresses, avoids negative emotions like the plague, and promotes a sense of emptiness and irritability in response to daily activities. It develops a sort of running commentary in the back of one's mind that vacuums up every negative detail and aspect of life, and ruminates on it, sometimes to an existential degree which is where suicidal ideation and crushing hopelessness comes into play. This leads to a perpetually preoccupied and disturbed state of attention that can rarely focus, and lacks the clarity and will to eat, sleep and attend to relational stuff like conflicts.

Quick Tangent: It should be noted that depression does not just operate in a vacuum. It's not as if life is great on the outside but a depressed person remains blind to it, trapped in some internal prison of warped reality. The depression seeps through life and slowly but surely transforms the external reality into a state of horror that matches the pre-existing internal reality. In other words, depressed people start to do things that make their environment incredibly depressing. This happens in myriad, complex ways.

A prime example of this is the idea of contagion. One important and realistic element of depression, which the film admirably highlights, is that depression can spread like wildfire and infect those within the familial unit or social support network. Walter's family practically catches his depression like the flu. His wife becomes edgy, lonely and skeptical. His adolescent son begins to act out (including a particularly disturbing tendency to self-destruct by banging his head against the wall), and despises his father so much that he compiles a collage of Post-Its listing all of the traits they share, so that he can eradicate them one by one.

You can see how depression can create an ever-deepening grave. Walter, who is already feeling paralyzed by his depression and barely able to contend with routine pressures, must now cope with an angry and alienated family.

Circling back to Walter's narrative, he clearly has a depressed internal voice operating within him. We see it vividly albeit sporadically throughout the movie. We watch as he wrestles with and suffers from it. For instance, whenever he's asked to think about the consequences of his past depressive actions or relax his guard and express negative emotions the depressed voice begins to shout - and life becomes the chaotic and unbearable mess that depression presupposes. The scene that starts with a romantic and mellow anniversary dinner but ends with a profane protest and volatile exit is a case in point.