[quote name='project_c' timestamp='1459944492' post='3021094']We don't have to use a clock to tell the time, we could just use the sun and our gut feelings, we don't have to use a thermometer or look at weather reports, we could just go outside and see what happens, but there are things which help us with these tasks, so we use them to make life a bit easier to navigate. That's all.
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Quite. I don't need to get on the scales to know I have a "muscular frame...'