Your ear can discern the slightest perceptible sound, even through the shrillest of noises.
Around 7.5 million commuters cram themselves into local trains every day and the fledgling metro and monorail are unlikely to make a perceptible difference in the near future.
British Columbia has just run a remarkably successful five-year experiment in carbon pricing, with a revenue-neutral carbon tax that not only substantially reduced emissions but included a perceptible rise in jobs and growth.
As Kingsley Amis put it: "The slightest and most banal coincidence or point of resemblance, or even just- perceptible absence of one, unworthy of a single grunt of interest, gets called 'ironical'ironical
The slowdown in the Chinese economy has had a perceptible impact on world demand for oil, while there has been a dramatic increase in the supply coming onto the market – the most obvious example being the fracking phenomenon in the US.
The best estimate for total man-made radiative forcing in 2011 is 43% above 2005 levels.Of course, more heat does not necessarily equal perceptible climate change.
Several studies suggest that immigration has made a perceptible contribution to this decline.And the other big difference between now and a century ago?
Dignitaries in robes and turbans communicated with barely perceptible flickers of the eye.
The dollar has slid, but there has been no painful financial crash, no dramatic rise in long-term interest rates, no perceptible impact on America's asset markets (the Dow Jones Industrial Average is up almost 5% since the election).
In such an environment, it is not surprising that existential angst in various forms, religious and secular, is now perceptible across Iranian society.
Medium-sized firms continued to contract, though at a barely perceptible rate.
