Eratosthenes: Right Time, Right Place, and Right Tools

Eratosthenes of Cyrene was born in the third century BC. He used his extensive knowledge and tools to measure Earth's circumference with an estimated error of less than two percent. The way he did it requires a little trigonometry, but if you want to dig deeper into this story, we used Douglas Hubbard's book "How to Measure Anything: Finding the Value of Intangibles in Business".

Eratosthenes was the head curator for the famous ancient library of Alexandria. He probably got to this post because he liked to read a lot. On a warm summer day in Alexandria, Eratosthenes read a book about a city about 600 miles south of Alexandria. The paper claimed that on that same day of the year, at a particular time of the day, the sun shined down on the well and without shadows, onlookers could see the clear water at the bottom. Eratosthenes looked around, found a well in his city, and noticed that there were shadows in the Alexandrian wells at the time given in the book. From this, he concluded that, as proposed by many before him, the Earth had to be round. He knew if he measured the length of the shadows of a stick of a chosen length in both cities on the day above and time, he could derive the curvature of the spherical Earth. The stick placed in Syene (the southern town) did not have a shadow, so he only needed the length in Alexandria to calculate Earth's curvature. If he could measure the distance between the two cities precisely, he could extrapolate this distance and this curvature to figure out the circumference of the Earth. And guess what? He did.

The lessons from Eratosthenes's achievements are many and allow us to go into a few more that can help entrepreneurs. First and foremost, be ready and keep up with your firm's ecosystem. Read everything you can about your business, be aware of your industry up and down the stream, and learn as much about your customers. The tale above is a simple version, but the lesson remains: Only those prepared will be able to take advantage of opportunities. At Finply, we want to help you think critically about this by segmenting your revenue streams. Our revenue app is fast, which will enable founders to create multiple models in little time which helps them find the most important drivers and risks of their business.

Secondly, the right tool can save you a lot of time and work. Imagine another way to get at Eratosthenes' measurement at the time. It would probably entail sailing and walking around the world, which, as far as we know, was impossible or prohibitively costly. The right way was using knowledge and math to figure out this problem. In the same way, our apps provide fast and precise tools to estimate your revenue. They are not a multifaceted spreadsheet, but rather concise automation that gets the output you need, quickly and accurately.

Finally, a good approximation calculated in a short period is slow and costly, but a precise estimate. Finply exists to give entrepreneurs their valuable time back. We want you to figure out critical aspects of your startup, not stressing whether a given cell in a convoluted spreadsheet is correct. We also give you the power to adapt. If a segment is no longer valid or is growing faster than you thought, you can change this in seconds and be sure that the resulting projections will accurately reflect the modifications.

To get started using Finply, head over to our signup page.

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