h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I reckon one big problem with psychology, philosophy, or any other subjects that claim some special insight into thought is when people go straight from school to study them at university, before they've really learnt enough about reality as an adult.
Some (*not* all) people start taking their particular brand of descriptive language *way* too seriously, and become convinced that they are they the chosen ones who really understand all thought in a way nobody else can.
From that point on, some start to filter everything they see in the real world through the terminology they've been taught, which means they're often not capable of realising when their world view is inadequate, or even plain wrong.
Language taken too seriously can be a real prison for thought.
To (probably mis-)quote Lao Tse, 'Once there are words, one also needs to know when to stop'