Imagine you are facing a choice between three options in a game, a business decision, or even your lunch menu. You evaluate them using a utility function like:
\[U = \frac{A \cdot B}{C \cdot D}\]Where each variable represents a meaningful factor:
Here is your set of options:
| Option | A (Benefit) | B (Bonus) | C (Cost) | D (Difficulty) | Utility $U = \frac{AB}{CD}$ |
|---|---|---|---|---|---|
| 1 | 10 | 2 | 5 | 1 | $\frac{10 \cdot 2}{5 \cdot 1} = 4$ |
| 2 | 9 | 2 | 3 | 1 | $\frac{9 \cdot 2}{3 \cdot 1} = 6$ |
| 3 | 12 | 2 | 8 | 1 | $\frac{12 \cdot 2}{8 \cdot 1} = 3$ |
Now observe: even though $B = 2$ and $D = 1$ for every option, the utility values still differ, because $A$ and $C$ vary. But because $B$ and $D$ are constant, we can simplify the function:
\[U = \frac{A \cdot 2}{C \cdot 1} = 2 \cdot \left(\frac{A}{C}\right)\]Since the multiplier (i.e. scalar) $2$ is the same for every option, it does not affect which option is best. So you can mentally reduce the utility to:
\[\text{Effective comparison: } U = \frac{A}{C}\]Now your decision feels simpler: you are just comparing benefit-to-cost ratios, even though the original function was more complex.
But here is the key insight:
The available options create a local illusion of simplicity by flattening the
utility landscape.
This illusion of simplicity happens when the set of options lacks variability across certain dimensions. You are not making a simpler decision because the world got easier — you are just looking at a flatter part of it.
What you have encountered is a phenomenon we might call local utility flattening. The full utility function still depends on four variables. But in your current local context, some of those variables are not changing, so they drop out of your attention.
This gives the illusion that the decision is simpler or that only some factors “matter.” But it is only because the other variables are currently not offering any contrast.
If tomorrow, new options appear where $B$ or $D$ vary wildly, you will suddenly need to re-engage with the full complexity of the utility function again.
This illusion of simplicity has real psychological effects:
Always remember:
A utility function only simplifies when you narrow the space of variation
That simplification is not “real” in the global sense — it is a local phenomenon. And mistaking a local simplification for a structural one can lead to flawed strategies or design choices.
In life, games, and systems thinking:
What seems simple might just be temporarily flat.