And one leading authority says that these intensely powerful mental events can be not only harnessed but actually brought under conscious control, to help us sleep and feel better.
The brain is as active during REM (rapid eye movement) sleep — when most vivid dreams occur — as it is when fully awake, says Dr. Eric Nofzinger at the University of Pittsburgh.
Do you remember all those years when scientists argued that smoking would kill us but the doubters insisted that we didn't know for sure? That the evidence was inconclusive, the science uncertain? That the antismoking lobby was out to destroy our way of life and the government should stay out of the way?
But science does provide us with the best available guide to the future, and it is critical that our nation and the world base important policies on the best judgments that science can provide concerning the future consequences of present actions.
There are upsetting parallels today, as scientists in one wave after another try to awaken us to the growing threat of global warming.
The latest was a panel from the National Academy of Sciences, enlisted by the White House, to tell us that the Earth's atmosphere is definitely warming and that the problem is largely man-made.
This may be because some people do not have the genes necessary to generate particular smell receptors in the nose.
Just as on smoking, voices now come from many quarters insisting that the science about global warming is incomplete, that it's OK to keep pouring fumes into the air until we know for sure.
So, if the provinces want to run the health-care show, they should prove they can run it, starting with an interprovincial health list that would end duplication, save administrative costs, prevent one province from being played off against another, and bargain for better drug prices.
They can hope that, if one province includes a drug on its list, the pressure will cause others to include it on theirs.
However, it has been found that even people insensitive to a certain smell at first can suddenly become sensitive to it when exposed to it often enough.
Humans are often thought to be insensitive smellers compared with animals, but this is largely because, unlike animals, we stand upright.
This means that our noses are limited to perceiving those smells which float through the air, missing the majority of smells which stick to surfaces.
A small step has been taken in the direction of a national agency with the creation of the Canadian Co-ordinating Office for Health Technology Assessment, funded by Ottawa and the provinces.
That's one reason why the idea of a national list hasn't gone anywhere, while drug costs keep rising fast.
Perhaps they should read what he had to say about drugs: "A national drug agency would provide governments more influence on pharmaceutical companies in order to constrain the ever-increasing cost of drugs."
So when the premiers gather in Niagara Falls to assemble their usual complaint list, they should also get cracking about something in their jurisdiction that would help their budgets and patients.
The explanation for insensitivity to smell seems to be that the brain finds it inefficient to keep all smell receptors working all the time but can create new receptors if necessary.
The brain finds it best to keep smell receptors available for unfamiliar and emergency signals such as the smell of smoke, which might indicate the danger of fire.
This entails reducing our dependence on the North American market, whose programs relate to experiences and cultural traditions which are different from our own.
Creating a "European identity" that respects the different cultures and traditions which go to make up the connecting fabric of the Old Continent is no easy task and demands a strategic choice — that of producing programs in Europe for Europe.
This alone demonstrates that the television business is not an easy world to survive in, a fact underlined by statistics that show that out of eighty European television networks, no less than 50% took a loss in 1989.
Moreover, the integration of the European community will oblige television companies to cooperate more closely in terms of both production and distribution.
In Europe, as elsewhere, multi-media groups have been increasingly successful: groups which bring together television, radio, newspapers, magazines and publishing houses that work in relation to one another.
In dealing with a challenge on such a scale, it is no exaggeration to say "United we stand, divided we fall."
This also involves the agreements between European countries for the creation of a European bank for Television Production which, on the model of the European Investments Bank, will handle the finances necessary for production costs.
Television is one of the means by which these feelings are created and conveyed — and perhaps never before has it served so much to connect different peoples and nations as in the recent events in Europe.
That means a higher proportion of what is in the sea is being caught, so the real difference between present and past is likely to be worse than the one recorded by changes in catch sizes.
Their methods do not attempt to estimate the actual biomass (the amount of living biological matter) of fish species in particular parts of the ocean, but rather changes in that biomass over time.
According to their latest paper published in Nature, the biomass of large predators (animals that kill and eat other animals) in a new fishery is reduced on average by 80% within 15 years of the start of exploitation.