The only certitude in life is change (And that change isn't inherently good or bad)
“There’s never two of anything” -Mrs. Sook in Truman Capote’s A Christmas Memory
“When you love someone, you do not love them all the time, in exactly the same way, from moment to moment. It is impossibility. It is even a lie to pretend to. And yet this is exactly what most of us demand. We have so little faith in the ebb and flow of life, of love, of relationships. We leap at the flow of the tide and resist in terror its ebb. We are afraid it will never return. We insist on permanency, on duration, on continuity; when the only continuity possible, in life as in love, is in growth, in fluidity – in freedom, in the sense that the dancers are free, barely touching as they pass, but partners in the same pattern.” -Anne Morrow Lindbergh in Gift from the Sea
“The only real security is not in owning or possessing, not in demanding or expecting, not in hoping, even. Security in a relationship lies neither in looking back to what was in nostalgia, nor forward to what it might be in dread or anticipation, but living in the present relationship and accepting it as it is now. Relationships must be like islands, one must accept them for what they are here and now, within their limits – islands, surrounded and interrupted by the sea, and continually visited and abandoned by the tides.” -Anne Morrow Lindbergh in Gift from the Sea
“Impermanence is the goodness of reality. Just as the four seasons are in continual flux, winter changing to spring to summer to autumn; just as day becomes night, light becomes dark and light again—in the same way, everything is constantly evolving.” –Pema Chodron in When Things Fall Apart
“The truth is that things don’t really get solved. They come together and they fall apart. Then they come together again and fall apart again. It’s just like that. The healing comes from letting there be room for all of this to happen.” –Pema Chodron in When Things Fall Apart
“…For as was true of all human effort, there was never advancement. Everything added meant something lost, and about as often as not the thing lost was preferable to the thing gained, so that over time we’d be lucky if we just broke even. Any thought otherwise was empty pride.” -Charles Frazier in Cold Mountain
“This too shall pass.” –Sufi Poets, exact origin unknown.
"The opposite of faith is not doubt, but certainty." -Anne Lamott
"The hero is the champion of things becoming, not of things become, because he is. 'Before Abraham was, I AM.' He does not mistake apparent changelessness in time for the permanence of Being, nor is he fearful of the next moment (or of the 'other thing'), as destroying the permanent with its change. 'Nothing retains its own form; but Nature, the greater renewer, ever makes up forms from forms. Be sure there's nothing perishes in the whole universe; it does but vary and renew its form.' Thus the next moment is permitted to come to pass." -Joseph Campbell in The Hero With A Thousand Faces
"A huge percentage of the stuff that I tend to be automatically certain of is, it turns out, totally wrong and deluded." -David Foster Wallace in This is Water
Personal observation from the macro to the micro helps to elucidate this idea. The obvious is in the form of changing seasons and daily weather patterns. The more subtle comes from paying attention by practicing mindfulness (which means being in the present moment) which allows you to observe your thoughts floating in and out and your heart experiencing the full spectrum of emotions.