Originally Posted by BBassett

How far do you think any of them would have gotten without "the science of Navigation"? The Phoenicians followed coastlines when they could and used Ursa Minor constellation, called by ancient writers the “Phoenician Star” and now known as Polaris or the North Star when they wandered away from shore. I agree that early humans traveled the planet and bet that they would have agreed with me on the marvel of GPS. Do you think mankind didn't need an Astrolabe back in "the good old days" or it's big brother a Sextant either? The early astrolabe was invented in the Hellenistic world by Apollonius of Perga, around 220 BC or in 150 BC and is often attributed to Hipparchus and they weren't the first tools invented by man to help him "stumble around in the dark". But then in this environment, if I were to proclaim toilet paper to be a great achievement of man someone here would scoff and boast how they use "reusable" corncobs.

Additionally to all you that point out that a cell phone is all you need, or "good enough", it has at least one GPS also.