I've been reading Dr Gene Wallenstein's book slowly, because I'm not as up on the minutiae of brain receptors and human evolutionary development as perhaps I should.
Likely, neither are you. Hey, we have busy lives, right? So let me summarise part of what he says in this biological study of where pleasure comes from.
The human brain transits information and processes information by way of a massively complex system of biochemical transmitters and receptors.
Different receptors respond to different biochemicals, and hence are known as systems. Some of these biochemicals have cognate chemicals (ie they function the same as the body-built versions) in the real world.
Four systems appear to govern pleasure. The mesolimbic dopamine system is primarily in charge of wanting.
Then there appears to be three systems that oversee liking, the reinforcement mechanism of pleasure. According to the good doctor, these are the opioid system, the cannabinoid system and the GABA-benzodiazapene system.
Yes, you read that right. The human pleasure system rewards us (the liking half of the wanting and liking equation) with natural opioids, cannabinoids and benzodiazapene.
You may have guessed at the real-world cognates of those body-generated biochemicals: smack, weed and your classic tranquilisers.
Is it any wonder that drug addiction is so difficult to treat and so misunderstood by the populace in general, when the human brain rewards itself with substances which can now be bought on a street corner for a few quid in highly potent (if not downright toxic) forms?
But for all the poetry and lyrical words we opine about our human happinesses and the things we take pleasure in, ultimately pleasure comes down to a shot of brain-brewed smack, weed or tranks.
Even if what you're actually getting high on is a beautiful sunset, sex or a bar of chocolate.
There's a sobering thought, eh?