Money that is saved or not spent is as valuable as money that is earned through work; frugality is equivalent to income.
This phrase is often attributed to Benjamin Franklin, though he actually wrote 'a penny saved is twopence dear' in his 1737 Poor Richard's Almanack. The modern version evolved over time, simplifying Franklin's more complex economic observation into a straightforward lesson about the value of thrift.
What's mathematically interesting about this phrase is that it's actually understating the case - a penny saved is often worth more than a penny earned because earned income is typically subject to taxes. This makes the wisdom even more profound than it initially appears, though few people consider this when using the phrase.
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