Diminishing Sensitivity

The psychological principle that the perceived difference between two stimuli decreases as their absolute magnitude increases. The difference between $10 and $20 feels enormous; the difference between $1,010 and $1,020 feels trivial—even though both are exactly $10. Weber's Law formalizes this: perception is proportional to the RATIO of change, not the absolute change. In business: a $5 price increase on a $20 product feels outrageous (25%); the same $5 increase on a $200 product feels negligible (2.5%). In risk: losing $1,000 from $10,000 feels devastating; losing $1,000 from $1,000,000 is barely noticed.

When to use it

When pricing decisions need to account for perceived vs. actual price sensitivity; when negotiating and need to understand how concessions will be perceived; when motivational interventions need to produce perceived progress; when communication about changes needs to account for the baseline magnitude.

How it can help

Understand that your sensitivity to changes DECREASES as the baseline increases. This has direct implications for pricing (relative changes matter more than absolute ones), for negotiation (the same concession feels bigger early in a negotiation when amounts are small), and for motivation (the same performance improvement feels more significant when you're starting from a lower base). Use this strategically: deliver bad news when the baseline is already high (it'll feel smaller) and deliver good news when the baseline is low (it'll feel bigger).