Put very simply (because I only understand it in a simplistic and trivial way, and not because I'm dumbing down for my handful of readers) science progresses because of the falsification of existing theories.
In the giant laboratory that is the universe, experiments are conducted and tentative hypotheses drawn up based on the results of the former. To be truly scientific, though, the hypothesis requires something which can later falsify it - the seeds of its own destruction.
Hence, all cats are black is a legitimate scientific statement, based on the observational evidence collected during my walk home from work last night. To falsify it, all that is needed is a single example of a non-black cat, and my careful drawing-up of a feline worldview is dead in the water. I can stave off defeat for a while by claiming that you must have been on drugs (ie the instrument you used when you conducted your experiment was faulty) or that the 'cat' you saw was just a shadow - a trick of the mind after a stressful day.
As the evidence mounts, though - ginger cats, brown ones, grey ones with stripes - I am forced to concede that my scientific statement (that I staked my career on, no less) is fit only for the bin, and retire to the margins with my reputation utterly in tatters.
The damning thing here is the single example of falsification which brings, in principle, the whole thing crashing down. In our everday lives, the margin for error is greater before we declare that we are in the midst of a crisis. It might take three or four late arrivals home before we begin to fear that our partner is having an affair; it takes a few heavy defeats at the start of a season for us to conclude that our football club is on a fast-track to relegation; several significant errors are required at work before the boss asks: is everything alright at home?
I wonder if we need to be more ruthless, like scientists, in order to limit the damage early. People are good at spotting patterns, and the natural thing is to extrapolate them, asserting that what holds today holds forever.
So when, towards the end of December, I got out of bed and the world around me held no interest, it was at that point - at the beginning of the 'first bad day in a row' - I should have sought help, for it falsified the hypothesis that 'everything is okay.' I didn't, of course, and now, a month down the line, the scarily passive has transformed into the comfortably numb, and I am less likely than ever to cry for help.
