Reasoning by induction
Reasoning by induction (inductive reasoning) involves observing a number of specific examples of something and then drawing generalised conclusions.
For example, if you have regularly upgraded your mobile phone and you have always been loyal to one manufacturer because you have found its phones to be very reliable, you have been reasoning by induction.
You may, of course, be right that your favoured manufacturer does produce very reliable mobile phones. But even if you are right, as a matter of logic your conclusion does not follow from your previous experience. A sample of perhaps half a dozen phones out of production runs of at least tens of thousands is far too small to justify any conclusions as to reliability across the board.Similarly, if half a dozen people go to a restaurant for a meal, and they all eat the same dishes, and they all have seriously upset stomachs a few hours later, there will be some grounds for concluding that the meal was to blame. However, before we could be reasonably confident of that conclusion, we would have to eliminate any reasonable alternative explanations. For example, we would need to know whether they had all eaten or drunk anything else (either very shortly before or very shortly after the meal) which could have been responsible for their upset stomachs. But, even if all the facts led you to the conclusion that the restaurant’s food caused their stomach upsets, you could not, as a matter of logic, conclude that it would always be unwise to eat at that restaurant. The stomach upsets may have been caused by one particular ingredient of the meal having being contaminated before it was received by the restaurant and the contamination may have been of a kind that the restaurant staff could not have detected.
Of course, it is impractical for anyone to be absolutely satisfied as to all the possible factors.
Changing the example, no matter how many white swans you see, there must always be the possibility that somewhere, and at some time, there is or has been a black swan. But we all live in a world where sheer practicality requires us to make decisions. The extent to which we can be confident that our conclusions are right will vary, depending on all the circumstances and may also be coloured by the practical consequences of acting in accordance with those conclusions and by how risk averse we are. Returning to our first two examples, the fact that many people would be tempted to play safe by always choosing one make of phone or always avoiding one specific restaurant can be said to reveal more about consumer psychology than it does about mobile phones and restaurants.Lawyers accommodate the most significant factor which makes inductive reasoning unreliable in more than one way. For example, the courts apply different standards of proof in criminal and civil cases (see pp. 4–5). Even more to the point, in the context of legal method, lawyers have developed the per incuriam doctrine, which may enable a later court to ignore what appears to a binding precedent if it is satisfied that the court which decided the earlier case did so in ignorance of a relevant proposition of law which was binding on it. (Per incuriam means through lack of care and is also discussed at p. 109.)
More on the topic Reasoning by induction:
- Reasoning by deduction
- Principles in legal reasoning
- Reasoning by analogy
- The importance of careful reasoning
- Introduction
- SUMMARY
- Having studied this chapter you should be able to explain:
- THE SC SILANIANUM IN THE SECOND CENTURY ce
- The Ambit of Reason According to Hume
- The last point to be treated here will be to show the most important functions principles fulfil in law.
- The Free-Rider Problem
- Concluding Remarks
- Introduction
- Destabilizing state sovereignty
- Three approaches and some ontological assumptions
- A functional approach: Power-conferring rules as reasons for action
- Table of Contents
- SUMMARY