Have tried many many substances though only pharmaceutical versions of opiates and methamphetamines which are low dose compared to recreational use. Deep first jhana is much more like a full body orgasm that lasts for anywhere from a few minutes to a few hours (I have personally experienced up to 10-15 minutes, hard to judge time, didn't have a clock at the time, can only enter them on demand on retreat.) This is much more pleasureable than drugs on the pure physical pleasure and contentment axes, though psychedelics + mdma can lead to insights that are a different axis of pleasure/happiness. I imagine that high dose opiates hit many of the same dimensions of first jhana, but with the problem of dullness that scales with dose, whereas jhana is vivid.
Have tried many many substances though only pharmaceutical versions of opiates and methamphetamines which are low dose compared to recreational use. Deep first jhana is much more like a full body orgasm that lasts for anywhere from a few minutes to a few hours (I have personally experienced up to 10-15 minutes, hard to judge time, didn't have a clock at the time, can only enter them on demand on retreat.) This is much more pleasureable than drugs on the pure physical pleasure and contentment axes, though psychedelics + mdma can lead to insights that are a different axis of pleasure/happiness. I imagine that high dose opiates hit many of the same dimensions of first jhana, but with the problem of dullness that scales with dose, whereas jhana is vivid.