It is said that all futures are predictable by the new logic of science if we only knew enough about complex phenomena to be able to strip them down to that which can be expressed in mathematical terms. Of course no one professes to be able to calculate the curve of the whole, or to have worked out a quantitative statement of many of the phenomena of life. But it is a scientific faith that it might conceivably be done. This seems to me to be merely saying that we could reduce the universe to reason if we only could do it, which is tautology. I am not sure that a universe so reduced would be anything more than a bare system of thought about only one aspect of the universe. But scepticism here is as distasteful to many scientists as the scientists’ own scepticism is distasteful to theologians. I am not asserting dogmatically that we cannot know truth or the nature of reality. I am not suggesting that we cannot be educated without ending in universal scepticism or agnostic negation. It seems to me that we have, or can have, such knowledge as will make our intellects fairly adequate instruments in the performance of their proper functions. But I do not see what such functioning has to do with ascribing finality to our beliefs or trying to legislate for all possible worlds. I am not suggesting an attitude of despair in the pursuit of truth, but am trying to state the very reason for any learning at all, for what is the use of it if we know it all before we start? Education may not end in doubt, but it ends when a man stops doubting. But why speak of the end of a process that should continue through life? As I see it, the process is more often discontinued at the point of some fictitious certainty than in any moment of doubt. Doubt, the willingness to admit that conjecture is subject to revision, is a spur to learning. The recognition that our truths are not copies of eternal realities but are human creations designed to meet human needs, puts one in a teachable frame of mind. And the discovery that thinking may be creative makes intellectual activity interesting. Much has been written by indoctrinators about the wretchedness of the dogmatic sceptic. I wonder how these writers, themselves so innocent of doubt, know so much about him. I have never found such a man. I do not believe he ever existed. There are writers who question things that most men do not even know exist, compared with whom professional “freethinkers” are often naïve. But such writers are often gentle and cheerful spirits whose minds are not at all paralyzed by doubt, but are active, subtle, stimulating.