the future has already happened

One of the most difficult to deny realities is the perceived shift from future to past tense.  Despite some solid Physics that shows that time does not exist as we experience it, we humans do indeed perceive and remember, at the least, difference.  The perception of time is inseparable from this recognition of difference: the hour hand has moved, time has passed; slowly crow feet form from smiling, I have aged, time has passed; the steady accumulation of years of practice making a virtuoso; the meal that was in front of me is now inside me.

trends

What else is invisible?  To me, trends seem to be invisible.  The recognition of a trend is at once dependent on noticing rhythm and/or frequency.