As Donald Trump's bad weekend descended into an equally chaotic week, California congresswoman Karen Bass launched a petition demanding that he receive a mental health exam.

Shared on Change.org and reported by the Los Angeles Times, Bass' petition circulated Twitter on Wednesday under the hashtag #DiagnoseTrump.

The trend quickly ignited a heated debate that spanned beyond the psychological state of the Republican candidate.

The hashtag's critics asserted that describing Trump's erratic behavior with a shrink's toolkit further stigmatized mental health illness and those actually impacted by it.

Others suggested that we may turn to psychological vocabulary because the words that most accurately describe 'the problem with Trump' have been used so many times they no longer shock or satisfy us.

This can feel especially frustrating when those labels — bigot, racist, etc — seem like they should be entirely disqualifying, and Trump has yet to be disqualified.

Time and time again, Trump manages to defy conventional politics and basic social norms. Even in the past few days, his actions and comments — feuding with both a Gold Star family and an entire Pennsylvania town, sloppily lying about his communications with NFL about debate scheduling, taking petty shots at members of his own party, belittling Michael Bloomberg's golf shot, and suggesting that Florida's escalating Zika was "under control" thanks to Gov. Rick Scott, just to name a few — seem to point to something bigger than a political problem.

Yet, addressing Trump solely as a uniquely bizarre or offensive individual is also somewhat unsatisfying.

When Trump seems to require us to throw out the political playbook, we often turn to a psychiatric one — the Diagnostic and Statistical Manual of Mental Disorders (DSM).

In her petition, Bass asserts that Trump fits the profile for Narcissistic Personality Disorder (NPD). She is not the first person to suggest this.

Bass writes:

"Donald Trump is dangerous for our country. His impulsiveness and lack of control over his own emotions are of concern. It is our patriotic duty to raise the question of his mental stability to be the commander in chief and leader of the free world. Mr. Trump appears to exhibit all the symptoms of the mental disorder Narcissistic Personality Disorder (NPD)."

Whether or not it is accurate or ableist to diagnose Trump with NPD or anything else — as various journalists have done recently and throughout his political run — it's worth asking why labeling him feels helpful or necessary.

Arm chair psychology, as this impulse is known, often pops up during high-profile news tragedies, Curtis Brainard points out in a piece about the coverage of the 2012 Aurora, Colorado movie theater shooting, published in the Columbia Journalism review. Trump isn't responsible for a tragedy in a literal sense, but his motives can elude us and appear similarly random.

Sometimes, we begin guessing — and shrinking — when we simply have said all that we actually know, Brainard suggests.

Trump often resembles a force of chaos.

In a 2011 paper published by the Canberra Jung Society, anthropologist Jonathan Marshall argued that chaos fills us with anxiety, so we try to explain it to make ourselves feel safer.

"Normally, we tend to flee from disorder and chaos; identifying chaos with evil and destruction," he writes. "We do our best to tidy it up and repress it."

Following this line of logic, slapping a recognizable label on Trump could make him appear less threatening than he does otherwise.

If it were possible to diagnose the 'Trump problem,' its unsettling symptoms — i.e. what he says and does — might feel easier to predict and safer to ignore.