Yet all technological systems include human as well as mechanical or electronic components. The ultimate control lies with people who understand in some depth what the purpose and nature of the control process are and the context within which the process operates. In addition to its intended benefits, every design is likely to have unintended side effects in its production and application.
On the one hand, there may be unexpected benefits. For example, working conditions may become safer when materials are molded rather than stamped, and materials designed for space satellites may prove useful in consumer products.
On the other hand, substances or processes involved in production may harm production workers or the public in general; for example, sitting in front of a computer may strain the user's eyes and lead to isolation from other workers. The effects of ordinary technologies may be individually small but collectively significant. Refrigerators, for example, have had a predictably favorable impact on diet and on food distribution systems. Because there are so many refrigerators, however, the tiny leakage of a gas used in their cooling systems may have substantial adverse effects on the earth's atmosphere.
Some side effects are unexpected because of a lack of interest or resources to predict them. But many are not predictable even in principle because of the sheer complexity of technological systems and the inventiveness of people in finding new applications. Some unexpected side effects may turn out to be ethically, aesthetically, or economically unacceptable to a substantial fraction of the population, resulting in conflict between groups in the community. To minimize such side effects, planners are turning to systematic risk analysis.
For example, many communities require by law that environmental impact studies be made before they will consider giving approval for the introduction of a new hospital, factory, highway, waste-disposal system, shopping mall, or other structure.
Risk analysis, however, can be complicated. Because the risk associated with a particular course of action can never be reduced to zero, acceptability may have to be determined by comparison to the risks of alternative courses of action, or to other, more familiar risks. People's psychological reactions to risk do not necessarily match straightforward mathematical models of benefits and costs.
People tend to perceive a risk as higher if they have no control over it smog versus smoking or if the bad events tend to come in dreadful peaks many deaths at once in an airplane crash versus only a few at a time in car crashes. Most modern technological systems, from transistor radios to airliners, have been engineered and produced to be remarkably reliable.
Failure is rare enough to be surprising. A system or device may fail for different reasons: because some part fails, because some part is not well matched to some other, or because the design of the system is not adequate for all the conditions under which it is used.
If failure of a system would have very costly consequences, the system may be designed so that its most likely way of failing would do the least harm. Examples of such "fail-safe" designs are bombs that cannot explode when the fuse malfunctions; automobile windows that shatter into blunt, connected chunks rather than into sharp, flying fragments; and a legal system in which uncertainty leads to acquittal rather than conviction. Other means of reducing the likelihood of failure include improving the design by collecting more data, accommodating more variables, building more realistic working models, running computer simulations of the design longer, imposing tighter quality control, and building in controls to sense and correct problems as they develop.
All of the means of preventing or minimizing failure are likely to increase cost. But no matter what precautions are taken or resources invested, risk of technological failure can never be reduced to zero.
The expected importance of each risk is then estimated by combining its probability and its measure of harm. The relative risk of different designs can then be compared in terms of the combined probable harm resulting from each. The earth's population has already doubled three times during the past century.
Even at that, the human presence, which is evident almost everywhere on the earth, has had a greater impact than sheer numbers alone would indicate. Use of that capacity has both advantages and disadvantages. On the one hand, developments in technology have brought enormous benefits to almost all people. On the other hand, the very behavior that made it possible for the human species to prosper so rapidly has put us and the earth's other living organisms at new kinds of risk. The growth of agricultural technology has made possible a very large population but has put enormous strain on the soil and water systems that are needed to continue sufficient production.
Our antibiotics cure bacterial infection, but may continue to work only if we invent new ones faster than resistant bacterial strains emerge. Our access to and use of vast stores of fossil fuels have made us dependent on a nonrenewable resource. In our present numbers, we will not be able to sustain our way of living on the energy that current technology provides, and alternative technologies may be inadequate or may present unacceptable hazards.
Our vast mining and manufacturing efforts produce our goods, but they also dangerously pollute our rivers and oceans, soil, and atmosphere. Already, by-products of industrialization in the atmosphere may be depleting the ozone layer, which screens the planet's surface from harmful ultraviolet rays, and may be creating a buildup of carbon dioxide, which traps heat and could raise the planet's average temperatures significantly.
The environmental consequences of a nuclear war, among its other disasters, could alter crucial aspects of all life on earth. From the standpoint of other species, the human presence has reduced the amount of the earth's surface available to them by clearing large areas of vegetation; has interfered with their food sources; has changed their habitats by changing the temperature and chemical composition of large parts of the world environment; has destabilized their ecosystems by introducing foreign species, deliberately or accidentally; has reduced the number of living species; and in some instances has actually altered the characteristics of certain plants and animals by selective breeding and more recently by genetic engineering.
What the future holds for life on earth, barring some immense natural catastrophe, will be determined largely by the human species. Individual inventiveness is essential to technological innovation. Nonetheless, social and economic forces strongly influence what technologies will be undertaken, paid attention to, invested in, and used. Such decisions occur directly as a matter of government policy and indirectly as a consequence of the circumstances and values of a society at any particular time.
In the United States, decisions about which technological options will prevail are influenced by many factors, such as consumer acceptance, patent laws, the availability of risk capital, the federal budget process, local and national regulations, media attention, economic competition, tax incentives, and scientific discoveries. The balance of such incentives and regulations usually bears differently on different technological systems, encouraging some and discouraging others.
Technology has strongly influenced the course of history and the nature of human society, and it continues to do so. The great revolutions in agricultural technology, for example, have probably had more influence on how people live than political revolutions; changes in sanitation and preventive medicine have contributed to the population explosion and to its control ; bows and arrows, gunpowder, and nuclear explosives have in their turn changed how war is waged; and the microprocessor is changing how people write, compute, bank, operate businesses, conduct research, and communicate with one another.
Technology is largely responsible for such large-scale changes as the increased urbanization of society and the dramatically growing economic interdependence of communities worldwide. Historically, some social theorists have believed that technological change such as industrialization and mass production causes social change, whereas others have believed that social change such as political or religious changes leads to technological change. However, it is clear that because of the web of connections between technological and other social systems, many influences act in both directions.
For the most part, the professional values of engineering are very similar to those of science, including the advantages seen in the open sharing of knowledge. Because of the economic value of technology, however, there are often constraints on the openness of science and engineering that are relevant to technological innovation. A large investment of time and money and considerable commercial risk are often required to develop a new technology and bring it to market.
That investment might well be jeopardized if competitors had access to the new technology without making a similar investment, and hence companies are often reluctant to share technological knowledge. But no scientific or technological knowledge is likely to remain secret for very long.
Patent laws encourage openness by giving individuals and companies control over the use of any new technology they develop; however, to promote technological competition, such control is only for a limited period of time.
Commercial advantage is not the only motivation for secrecy and control. Psychology uses various research methods, but the most powerful is undoubtedly controlled experimentation, not because it is more objective or precise than other methods, but because it is uniquely capable of providing evidence of causal effects. The defining features of an experiment are manipulation of a conjectured causal factor, called an independent variable because it is manipulated independently of other variables, and examination of the effect of this on a dependent variable , while simultaneously controlling all other extraneous variables that might otherwise influence the dependent variable.
In psychological experiments, extraneous variables can seldom be controlled directly, partly because people differ from one another in ways that affect their behaviour. In , the British statistician Ronald Fisher discovered a powerful method of control called randomization. By assigning subjects or participants to an experimental group and a control group strictly at random, and then treating the two groups identically apart from the manipulated independent variable applied to the experimental group only , an experimenter can control, at a single stroke, for all individual differences and other extraneous variables, including ones that no one has even considered.
Randomization does not guarantee that the two groups will be identical but rather that any differences between the groups will follow precisely the known laws of probability. This explains the purpose and function of statistical significance tests in psychology. For any observed difference, a significance test enables a researcher to calculate the probability that a difference at least as large as the observed difference could occur by chance alone.
The researcher then knows what the probability is of such a large difference under the null hypothesis — the working hypothesis that the independent variable has no effect. If this immensely powerful idea were more widely understood, then people would be less vulnerable to illusory correlation , more sceptical about merely anecdotal evidence, and capable of interpreting findings from any survey research, case study, correlational study, observational study, or quasi-experiment with appropriate caution.
It is sustained by the increasingly popular doctrine that neuroscience can in principle replace traditional psychology, that it is already replacing traditional psychology, or in its strongest form that it has already replaced traditional psychology. This is a debilitating form of reductionism , based on the assumption that behaviour and mental experiences are closely correlated with neural processes, especially in the brain; but locating a mechanism in the brain does not amount to explaining the associated psychological phenomenon, as I can easily show with a Gedankenexperiment thought experiment and an example from nature.
First, imagine a super-intelligent alien trying to understand a working computer busy printing out my Dictionary of Psychology on a laser printer. Second, purposeful behaviour can occur naturally without any involvement of neural mechanisms. For example, the unicellular paramecium , found abundantly in stagnant ponds, moves about, avoids obstacles by swimming round them, gathers food, and retreats from danger.
It can turn round in a glass tube to escape, and it can even learn from experience, although some neuroscientists unsurprisingly question whether this is true learning. Yet a paramecium has no nervous system, and its single cell is not even a neuron ; therefore, it provides conclusive evidence that neuroscience cannot explain all forms of behaviour. Reference Terms. Related Stories. But environmental and cultural factors in these locations may be very different from The team invented a liquid-metal-inclusion based triboelectric nanogenerator, called Epitaxial lithium niobate LNO thin Have We Detected Dark Energy?
Scientists Say It's a Possibility.
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