Why Buddhism Is True (and sometimes re-listening to various podcasts with Bob; eg., Dan Harris' 10% Happier podcast).
To me, enlightenment would entail fully internalizing that all there is is matter and energy. Just physics. I know this is true intellectually, but I don't live my life as such.
If I could fully, truly internalize that simple fact, the consequences would be enormous*. Viscerally understanding that there is no free will - we are all just damaged biological robots - would be incredibly profound.
It took me many years to not get angry every time something like a computer malfunctioned. In the absolute happiest time in my life, I still swore at my computer. I still sometimes get upset when technology malfunctions, let alone people.
If I could fundamentally recognize that everything in the universe as simply the interaction of matter and energy, I would be liberated. I would, I think, have achieved as much enlightenment as possible.
Wish me luck. ;-)
*This isn't to say I wouldn't still try to reduce suffering. Even though it is just the product of the interactions of matter and energy, Suffering Is Bad. I think it is possible (and desirable) to distance myself from, say, my degenerative osteoarthritis pain (although it is hard to imagine being sanguine about a Crohn's attack). But that wouldn't change the fact that it is Good to reduce suffering.