コリングリッジの技術選択論 : 原子力発電を手がかりとして

New technologies appear constantly in rapid succession in the modern world of science and technology. Through development and diversification in technology, each technology poses large, divers and unpredictable risks to society. From the ethical point of view, effective ways to discern risky technologies are required in such a situation, to avoid negative social effects in advance. David Collingridge’s theory of decision-making provides a guiding principle to assess technologies. According to Collingridge, human understanding, analytical capacities and information acquisition　are so limited that no decision can be known to be correct in advance. After a decision has been made, it is threatened by the discovery of unexpected facts that may cause those who made the original decision to regret their choice. Collingridge maintains that incrementalism is the most effective way under such circumstances; new technologies should be adopted step by step through “trial and error learning”. However, technologies with their four properties of long lead-time, large unit size, capital intensity and dependence upon infrastructure, have a strong tendency to prevent trial and error learning. He calls these kinds of technologies “inflexible” and argues that such technologies should not be adopted, because they are highly likely to entail large economical and social costs. This paper aims to describe Collingridge’s theory in detail and to evaluate it as giving a basic insight about how to recognize risky technologies under great uncertainty, even though the effectiveness of this theory is essentially limited.