An advantageous reminder is that while we are blessed with the power of cognition, we remain biological creatures often at the mercy of our phylogeny. This is advantageous when we recognize it, and, when the instinctual, non-rational part of our brain does its job in ensuring the survival of our little puddle of the gene pool. The problem comes in that our instinctual brain lacks discernment and will veto our rational cortex when it perceives a threat.
Gary Marcus, in “Does your brain have a mind of its own?” (L.A. Times, May 4, 2008) offers a helpful explanation of how our brain plays against itself. An interesting read.