# Scientific Measurements Use Chains of Proxies All scientific measurements use chains of proxies. Each link in the chain is an additional source of error, and we can avoid fooling ourselves only by criticizing the theory of each link – which is impossible unless an explanatory theory links the proxies to the quantities of interest. That is why, in genuine science, one can claim to have measured a quantity only when one has an explanatory theory - an [Explanation](Explanations.md) - of how and why the measurement procedure should reveal its value, and with what accuracy. Why exactly do scientific measurements use chains of proxies? Can we not measure the entities we are interested in directly? No, for [All Observations are Theory Laden](All%20Observations%20are%20Theory%20Laden.md). Even simply viewing a print out of numbers on a screen involves interpreting crackles of electricity (nerve signals) inside our brains. Scientific instruments then just introduce further layers of indirectness. The measurement of a quantity is *meaningless* unless there is an explanatory theory that links the measured proxy to the quantity of interest. For instance, if I look through one end of a telescope and start observing specks of light on a dark background, I need to have an explanatory theory that says I am actually looking up at a cloudless night sky. If instead I was actually looking at a computer screen with a black background, then I would clearly have no ability to conclude *anything* about stars and planets. Similarly, consider trying to measure happiness. If we create a survey and have 1000 randomly selected people fill out, where one box is "Rate your level of happiness on a scale of 1 to 10", the box that they check is a *proxy* for happiness. Without an explanatory theory of how checked boxes relate to our quantity of interest, happiness, we have *no ability* to interpret the survey results with respect to happiness. All we can make are claims regarding checking boxes. For instance, maybe it turns out that people who tend to check higher numbers actually just have lower standards but are meaningfully less happy. And likewise those who check lower boxes are actually quite happy, but have too high of expectations. Without an explanatory theory - one that we can *criticize* - we cannot link these two quantities, happiness and checked boxes on paper, together. If we cannot criticize, we cannot [Error Correct](Error%20Correction.md). And if we cannot error correct, we cannot make [Progress](Progress.md). This is actually a quite deep phenomena that relies on the [Self-Similarity](Self-Similarity.md) of the universe: certain parts of physical reality resemble other parts. Scientific measurements rely on chains of self similarity. --- Date: 20250104 Links to: Tags: References: * []()