Now the geologists Thompson, Johnson, Jones and Ferguson state that our own layer has been ten thousand years forming. The geologists Herkimer, Hildebrand, Boggs and Walker all claim that our layer has been four hundred thousand years forming. Other geologists, just as reliable, maintain that our layer has been from one to two million years forming. Thus we have a concise and satisfactory idea of how long our layer has been growing and accumulating. Most scientists would like to see scientific advice used more in government decision-making and in all areas of public policy where science is salient, and many would welcome the opportunity to sit on expert review panels or scientific advisory committees. When it comes to taking such decisions in many areas of hazard and risk assessment, the traditional committee approach still holds sway. Often in a committee setting, however, the role of scientific uncertainty is not an item on the agenda, and seldom a prominent component of the discussion. But misunderstanding its importance or misstating its extent will contribute to poor decisions. The slow, deliberative committee process, seeking a wide range of opinions with majority voting on outcomes, offers some parallels with the scientific process itself, but only in as much as a show of hands can equate to strength of argument. But as a means of gathering expert opinion it is inadequate under many conditions, such as an urgent civil emergency arising from an incipient natural disaster such as a hurricane or volcanic eruption – situations demanding prompt scientific advice.