I see some scientists were doing some work on clinical depression.

Seeing as this is a fairly common problem, I say fair play to them.

Now I always thought that clinical depression was caused by enzymes or endorphins or some similar animal.  It seems logical that depression, being a brain related affliction should have its causes rooted in the brain?

However, one of these scientists had a brilliant idea.  "Let's examine the victim's shit" he cried.

Now I am no neurological expert, but even my feeble brain has difficulty grasping the logic of suddenly deciding to examine poo when the problem lies at the other end of the body, but then these bods seem to work on some strange planet where logic takes a different path.  Who am I to argue?

Anyhows they decided that poo was the answer and started doing some tests.

They found themselves a perfectly happy normal rat [though how a rat can be happy in a laboratory cage is a tad baffling].  They then got some shit from some poor depressant and proceeded to shove it up the rat's arse.  The rat showed symptoms of depression and anxiety.

"Eureka" the scientists cried.

Now call me a cynic if you will, but just for a moment imagine you are a normal happy person going about your business without a care in the world.  Suddenly for no apparent reason the hand of god reaches down and shoves half a ton of elephant shit up your hole.  Wouldn't you be depressed and anxious?

I know I would.