The direct and ultimate causation of the big bang responsible for the lineage and mutations of my ancient DNA over the course of eons, including but not limited to the genetic lottery and alien tinkering (subject to the same of course), in conjunction with acquired behavioral patterns and subsequent modifications resulting from physical interactions throughout my existence, and especially current meteorological conditions including but not limited to barametric pressure and - I can't emphasize this enough - gravitational forces... have all culminated in compelling my brain to manipulate my fingertips in such a way as to type:

Congratulations! Your post comes across as a masterclass mini-dissertation on the intersection of physics, biology and philosophy. It adds that Aunt Bea's captivating Sapolsky clip informs much of what I've typed. It's also handy because it lends desperately needed support every time I tell Flying Solo that "it's not my fault!" Thank you for that!