Opposite conclusions

Imagine two alternatives of a postal letter you receive from your bank with updates on the terms of service:

1. one-pager with a list of the changes briefly in legal terms, which you don’t understand

2. four pages illustrating the same changes in detail in legal terms, which you don’t understand

Which one would you find more reassuring?

Your reasoning for the first option could be that nothing relevant has changed if there is only a list that fits on one page. If the bank had changed something important, it would have made a long document.

For the second option, because the bank made such a long document, they must have sorted it all out, so it probably doesn't affect you.

The opposite can be said for both thought processes.

Still, the two reasonings and the opposites can be true. In reality, we usually come up with one, and the others don't even cross our mind. This is because of heuristics that were shaped by our previous experiences and the context. The latter is crucial in leading to one of the two opposite lines of thought. For example, if you have recently made a significant investment, then your interest in terms of service is high, and your reaction would change.

Now think of two products with the same characteristics, but one costs 1.25x the other: which one would you choose?

It also depends on the risks associated with the product: if it is a commodity like paper, the majority will go for the least expensive, thinking “it costs more but the quality must be roughly the same”. If instead it is food, one can believe that there must be a reason why the price is lower, and if the quality of food is indeed inferior, it can affect your health.

Summarizing, the same event can spark diametrically opposite reasonings. Keeping in mind that the interpretation depends on the surrounding factors can help evaluate the soundness of our immediate reaction.

Note: For the postal letter example I took inspiration from the book Alchemy: the surprising power of ideas that don't make sense, by Rory Sutherland.