Using big cushions, I built my (now highly mobile) baby a rudimentary cave system with three entrances and one cul-de-sac. She flees from me into the cave, shrieking with laughter. If I am insufficiently persistent, she peeks out to check where the monster has gone. Lazy monster. She comes out to one of the entrances, so that she is easy to catch. If I catch her but am not satisfyingly monstrous, she just stares at me until I escalate – knocking her over, tickling briefly, grabbing her feet and dragging her towards me, or just saying rawr more loudly.
Sometimes I’m on my laptop and she, mid-crawl, looks back at me in what seems like a pointed way. I usually set the computer down, get on my hands and knees, and lumber after her. She bursts into giggles and speeds to the cave system for shelter.
Oh, her little face, shining with joy and mischief when I give her a particularly good fake scare. Chasing her through this little cave system is a top ten life experience for me, maybe even top five. And it’s interesting to think that she invites me to these running and hiding games in part because this childhood play was adaptive for animals at risk of predation. So much of our joy flows through evolutionary runnels that were carved by suffering.
The other example that comes to mind for me is consensual violence play in sex. I seem to be asexual these days, but before that happened, BDSM (both in real life and in fiction) was a great source of pleasure, and the handful of consensual non-consent orgies I’ve attended were some of the best sexual experiences of my life. My kinks are an uncomplicated source of joy for me, and/but it seems likely to me that this disproportionately female cluster of kinks is a rape adaptation. Premodern life was full of sexual coercion and it’s probably bad for your fitness if you’re too stressed out by rape. Ideally you want to avoid rape but have psychological outlet for sublimating the distress if it happens. Individuals like me, who got especially unsubtle mechanisms, can ride them to have peak experiences.