This morning, I told my class repeatedly, "Never send an email with a blank subject line." I forgot what I knew to be true: that the unconscious mind is really bad at listening to negatives. Some part of me heard "send an email with a blank subject line." And so, when I returned to my computer, I sent an email with a blank subject line.
Ouch. I had to avoid what I knew on at least two different levels to make one dumb mistake.
Everyone makes dumb mistakes. Everyone gets caught in the common failing of saying what we don't want - and thereby making it probable if not inevitable. We live in a world of "thou shalt nots" and they are hard to avoid.
Next class, I will tell my students: "Always begin by creating a subject line that catches the positive attention of your reader."