Reasoning draws a conclusion and makes us grant the conclusion, but does not make the conclusion certain, nor does it remove doubt so that the mind may rest on the intuition of truth, unless the mind discovers it by the path of experience.

In a certain sense all knowledge is inductive. We can only learn the laws and relations of things in nature by observing those things. But the knowledge gained from the senses is knowledge only of particular facts, and we require some process of reasoning by which we may collect out of the facts the laws obeyed by them. Experience gives us the materials of knowledge: induction digests those materials, and yields us general knowledge. When we possess such knowledge, in the form of general propositions and natural laws, we can usefully apply the reverse process of deduction to ascertain the exact information required at any moment. In its ultimate foundation, then, all knowledge is inductive—in the sense that it is derived by a certain inductive reasoning from the facts of experience.

Reasoning draws a conclusion, but does not make the conclusion certain, unless the mind discovers it by the path of experience.

Reasoning is a robust source of hope and confidence in a world darkened by murky deeds – past and present. It is not hard to see why this is so. Even when we find something immediately upsetting, we can question that response and ask whether it is an appropriate reaction and whether we should really be guided by it. Reasoning can be concerned with the right way of viewing and treating other people, other cultures, other claims, and with examining different grounds for respect and tolerance.

The inductive-reasoning system I have described above consists of a multitude of “elements” in the form of belief-models or hypotheses that adapt to the aggregate environment they jointly create. Thus it qualifies as an adaptive complex system. After some initial learning time, the hypotheses or mental models in use are mutually co-adapted. Thus we can think of a consistent set of mental models as a set of hypotheses that work well with each other under some criterion—that have a high degree of mutual adaptedness. Sometimes there is a unique such set, it corresponds to a standard rational expectations equilibrium, and beliefs gravitate into it. More often there is a high, possibly very high, multiplicity of such sets. In this case we might expect inductive reasoning systems in the economy—whether in stock-market speculating, in negotiating, in poker games, in oligopoly pricing, in positioning products in the market—to cycle through or temporarily lock into psychological patterns that may be non-recurrent, path-dependent, and increasingly complicated. The possibilities are rich.

There isn't anything really, in the last resort that isn't inductive. Even the laws of deductive logic have been established only by induction. ...We can't use deductive logic ...

Creative insight is not the final link in a chain of reasoning. If it were that, it would not strike us as inspired in its origin. Intuition is not the end, but part of an ever-developing and ever-dynamic process of realization. There is continual system of “checks and balances” between intuition and the logical method of discursive reasoning. Cognitive intuitions are not substitutes for thought, they are challenges to intelligence. Mere intuitions are blind while intellectual work is empty. All processes are partly intuitive and partly intellectual. There is no gulf between the two.

By induction we gain no certain knowledge; but by observation, and the inverse use of deductive reasoning, we estimate the probability that an event which has occurred was preceded by conditions of specified character, or that such conditions will be followed by the event. ...I have no objection to use the words cause and causation, provided they are never allowed to lead us to imagine that our knowledge of nature can attain to certainty. ...We can never recur too often to the truth that our knowledge of the laws and future events of the external world are only probable.

Demonstrative reasoning penetrates the sciences just as far as mathematics does, but it is in itself (as mathematics is in itself) incapable of yielding essentially new knowledge about the world around us. Anything new that we learn about the world involves plausible reasoning, which is the only kind of reasoning for which we care in everyday affairs.

It is by logic that we prove, but by intuition that we discover. To know how to criticize is good, to know how to create is better

Logical knowledge is indirect and symbolic in its character. It helps us to handle and control the object and its workings.

It is by logic that we prove, but by intuition that we discover. To know how to criticize is good, to know how to create is better.

Clarifying your thinking and explaining the origins of your ideas. (Why do I think this? What exactly do I think?) Challenging assumptions. (How do I know this is true? What if I thought the opposite?) Looking for evidence. (How can I back this up? What are the sources?) Considering alternative perspectives. (What might others think? How do I know I am correct?) Examining consequences and implications. (What if I am wrong? What are the consequences if I am?) Questioning the original questions. (Why did I think that? Was I correct? What conclusions can I draw from the reasoning process?)

most of the shaping of your mind remains forever unconscious. This is called implicit memory, and it includes your expectations, models of relationships, emotional tendencies, and general outlook. Implicit memory establishes the interior landscape of your mind — what it feels like to be you — based on the slowly accumulating residues of lived experience.