Abduction: The Third Type of Logical Thinking

When we think “logically,” many of us use induction and deduction. Whether the conclusion comes from the general principle or specific examples, we usually depend on principles, or what we observe. But there is another approach, where a constructive hypothesis is applied, called abduction.

On May 8th, we discussed the significances and how we apply abduction, based off of Yuji Yonemori’s Abduction: Kasetu to Hakken no Ronnri [The Logic of Hypothesis and Discovery].

Here are examples by Charles Sanders Pierce:

Deduction:

1. All beans from this bag are white.(principle)
2. These beans are from this bag.(case)
3. These beans are white.(result)

Induction:

1. These beans are (randomly selected) from this bag.(case)
2. These beans are white.(result)
3. All the beans from this bag are white.(principle)

Abduction:

1. All the beans from this bag are white.(principle)
2. These beans are (oddly) white. (result)
3. These beans are from this bag. (case)

As you can see, the case of the abduction is based off of a constructive hypothesis; it assumes the odd relationship between the beans and the bag.

The constructive way of understanding is similar. The constructive way of understanding is finding what the hidden rules (principle) behind an odd phenomenon (result) are by various methods (case.) It approaches the “oddness” of a phenomenon that is yet to be discovered, from a different paradigm. 

 

For example, during the process of creating pattern language, the writer must often abductively hypothesize what the solution(s) is in a given context and problems, because there is no definite principle or case that can be applied.

As so during the KJ method, one must abductively perceive the true attributes of 2 different experiences, in order to form groups. For example, while creating the Collaboration Patterns, “Respond to emails quickly” and “Exchanging emails is important” should not be grouped because they concern emails. When abduction is applied, “Respond to emails quickly” should rather be grouped with “feedbacks should be given constantly and immediately,” because they both concern the significance of responding and not so much about a communication software. 

 

We believe research in Keio University SFC requires thinking abductively. The essence of researching SFC is how to perceive what has been observed already from another perspective. As noted in the complex systems theory, in our complex society, it is critical not to focus on only one perspective; one must see the relationships between seemingly different fields. And to do so, one must not limit oneself to induction or deduction (because it has already been done) but apply abduction effectively.

For the second part of the class, we continued with the week before, and each student started creating their own videos. Each student brought in videos, pictures, music, and started creating their own, original video.

Contrary to the week before, where every student had the same videos to edit from, we could already see the diversity of creations, and their constructive way of understanding. Next, we will show the final products of some of the students, made from pure constructive understanding.

References

Yuji Yonemori, Abduction: Kasetu to Hakken no Ronnri [The Logic of Hypothesis and Discovery], Keisoshobo Pubshiling Co., 2007