I see from your article, “Sadness is Overrated,” that your viewpoint is similar to Mary Baker Eddy’s Christian Science. She argued that matter is an illusion and that diseases are mental errors rather than physical deficiencies. Likewise, you say negative emotions are illusory and happiness is the default psychological state.
That strikes me as untenable and based on word games. You imply, I think, that animals feel pain but not sadness. How could sadness be an artificial emotion if happiness or contentment were fundamental? Happiness is just as complex and particularly human as sadness. Emotions in general as we understand them derive from the human mind, so other animal species aren’t likely to feel any of them, neither sadness nor happiness. Who knows what they feel? That was the point of Thomas Nagel’s famous philosophical article, “What’s it Like to be a Bat?” We can’t really imagine an alien’s interior states without projecting ours onto them, because consciousness is metaphysically private.
Thus, if sadness and melancholy were errors of human decadence, so would be happiness and contentment. As I understand it, though, philosophy tends to make enlightened individuals more melancholy than happy or contented. That’s because the fundamental truths we discover upon philosophical reflection are inhuman and unappealing. We learn, for example, that the religions with their uplifting myths are so many flavours of arrant nonsense. We learn that our emergence as a species is accidental and pointless, that there’s no ultimate justice in the universe, nor any cosmic purpose of being alive.
With our brains, we’re too clever for our good. Just as children outgrow their enchanted state of naivety, adults who study science or philosophy tend to outgrow the conventional worldviews that reassure the masses by feeding them delusions. And the deluded masses are typically exploited by human predators and parasites, including religious gurus and other con men. That’s just one more appalling truth to nauseate philosophers.