Inflation & Deflation
Why Your Savings Are Lying to You
The number in your bank account has stayed the same, but something quietly stole a slice of it while you weren't looking.
The Idea
There are two versions of any amount of money: the nominal value, which is the number printed on the note or shown on the screen, and the real value, which is what that number can actually buy. Inflation is the process by which the gap between these two figures silently widens over time — and it does its best work precisely when you're not paying attention. The price level is the average cost of a broad basket of goods and services across an economy. When it rises, each unit of currency buys less of that basket than it did before. This isn't just an abstract statistical exercise — it means that holding money in a low-interest account during a period of moderate inflation is, in real terms, a loss. The number doesn't shrink, but its purchasing power does. You are, in effect, walking up a descending escalator. What makes this genuinely strange is that our intuitions are calibrated to nominal values. A pay rise of three percent feels like a gain. If inflation is running at four percent, it's actually a cut — a subtle one, but real. The economist Irving Fisher formalised this distinction in the early twentieth century, drawing a sharp line between nominal interest rates and real ones. The real rate, he argued, is the only rate that actually matters for economic decisions. Everything else is accounting flattery. Most of us, most of the time, reason in nominal terms. That's not stupidity — it's cognitive convenience. But it costs us.
In the World
In the mid-1960s, a skilled worker in the United Kingdom might have felt quietly prosperous. Wages were rising year on year, and the number on the payslip kept going up. What few people fully registered was that prices were rising faster. By the early 1970s, inflation had crept above ten percent, and by 1975 it peaked at nearly twenty-five percent. A worker who'd been careful enough to save a meaningful sum at the start of the decade found, by the middle of it, that their savings could buy roughly half what they once could. The nominal amount was intact. The real value had been roughly halved. The psychologist Amos Tversky, in a famous thought experiment, asked people whether they'd be more upset by a pay cut of five percent in a low-inflation environment, or a pay rise of three percent when inflation was running at eight percent. The second scenario is worse in real terms — a loss of five percentage points of purchasing power — but most people felt better about it. Tversky used this to illustrate what he called 'money illusion': the tendency to think in nominal rather than real terms. We anchor to the number, not the thing the number represents. This illusion isn't merely academic. It shapes how people negotiate salaries, evaluate investments, and make decisions about when to spend versus save. Entire generations have made major life decisions — buying property, planning for retirement — while reasoning from figures that looked solid but were, in real terms, quietly melting.
Why It Matters
Once you genuinely internalise the difference between nominal and real value, you start to see the world slightly differently — and more accurately. You stop treating the figure in your savings account as a fixed asset and start treating it as something that's in constant, slow competition with the price level. Some years it wins. Some years it loses. This reframe has immediate practical weight. It changes how you evaluate an interest rate on savings — not 'is this a positive number?' but 'does this outpace inflation?' It changes how you think about a pay negotiation. It changes how you read news about wage growth, housing prices, or pension returns. More broadly, it cultivates a habit of thinking in real rather than nominal terms — which is, quietly, one of the most useful mental moves in economics. It's the difference between seeing what's on the label and understanding what's in the tin. The two are often the same. But when they diverge, the divergence is almost always in a direction that costs you something — unless you're already watching for it.
A Question to Ponder
If inflation quietly erodes the value of money held still, what does that imply about the relationship between caution and risk in how you manage your finances?
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