are we there yet?

In its useful, static role, the horizon is an arbiter of space; assign it a numeric value in a perspective drawing, and one can draw in objects with believable proportions. In its metaphysical role, it's a tool for reflection to an observer. Go deeper: it's the edge of time on which we balance as we walk our lives, unrolling and revealing what only time will tell.
One summer dad drove us from Chicago to San Francisco on the not-finished Interstate 80 in our new Chevy. We were going to see mountains and ocean. My 5 yr-old flatland eyes trained on the horizon, waiting for the Disney-esque or Chuck Jonesian butte to appear. Every time my attention stalled, I'd ask "Are we there yet?" Poor mom and dad! That summer, horizon became linked to yearning: constantly there but out of reach, withholding but promising new information. We hurtled to California, toward our futures.