I'm a firm believer that use of good analogies is a reliable indicator of intelligence. The ability to convey a complex concept by comparing it to one easier to understand is the mark of a gifted communicator.
So, how would you go about describing the dangers of self-reflection when vexed?
When one is vexed, one must avoid meditating about oneself. One is like a man with jaundice: he must not study the map of the countries he is about to traverse—he would see everything in yellow. Yellow is the colour of Sweden, so he would believe that every country was Sweden, and if by chance the King of Sweden had set a price upon his head, he would be in despair: this despair would be the effect of his jaundice. And such is the effect from which I suffer every time I go to Grenoble; so much so that, on the last occasion, I almost entirely avoided thinking about my future.
—Stendhal to his sister Pauline, 17-Sep-1805
To the Happy Few: selected letters of Stendhal (trans. Norman Cameron) (1952)
…I'm reluctantly beginning to accept I'll never be recognised as a literary genius on a par with Stendhal.