You will die if you don’t eat, and you will die either if you eat excessively. In the Nicomachean Ethics, Aristotle describes that eating too much or too little has a bad consequences to our body. Hence, the correlation between eating and health is not linear.

In economics, no tax makes government has no revenue, no infrastructure, public health, education, and security. On the other side, charged 100% tax makes individual has no money, and there’s no reason to work, then economy collapse and government has no revenue. It’s clear that the government’s revenue and taxation is not linear either.

Linear vs Laffer Curve

In finance management, too much saving habit for retirement makes latter regret of not spent your youthful spending money for your own good. But excessively spending money makes you regret as well for not having retirement saving. Correlation between regretlessness and saving for retirement is not linear.

In software development, there’s always tradeoff, there’s always an opportunity cost on choosing between one approach besides another. Which one is better, build a bugs free solution but late delivery. Or build a simple, one day delivery but bugs are everywhere. The relation between the quality of being professional and the time taken to develop software with less bugs is also not linear.

It’s always naive to have a linear mindset. The world is not made in binary characteristic, linear correlation. There’s a lot example of it, I just only mention few. If there’s an optimal way, it must be somewhere in between. And it applies on every aspects.

Thinking in moderation means thinking in a way that nothing can be called as an optimal unless we believe that the extreme must not the answer of the optimal solution.