we only ever talk about ourselves
This hint is easy to understand but difficult to apply. We sometimes hear it in other forms like:
This hint asserts that there is no objective world "out there" but only the projections of our private and usually secret beliefs onto a very blank screen. The two words that cry out to be skipped while reading the hint are ONLY and EVER. It is these words that turn a humorous party quip like "ha ha gosh -- you seem to be talking about yourself" into a profound spiritual truth. How we view the world, its peoples, and their many interactions is precisely how we view ourselves. The world, in this context, is a very shiny mirror graciously made available for deep self-examination.
As a simple example, consider someone madly weaving from lane to lane, shaking a fist at each car he cuts off, while shooting dirty looks out his rear view mirror. If we could ask him about the other drivers out there, he would probably say they are rude and careless and should be denied drivers licenses! Other examples include the exhortations that psychiatrists are crazy, priests are sinners, and cops are "blue thieves.”
This hint is first because, without a profound understanding of it, we are locked into a life of blame, helplessness, and irresponsibility. Its understanding and application breathes life into the other four hints.