Programming languages are much more than tools; they are frameworks of thought. Breadth of knowledge beats being an expert in a single language hands down ever

Programming languages are much more than tools; they are frameworks of thought. Breadth of knowledge beats being an expert in a single language hands down every time. If you are not familiar with other programming languages and concepts then you will not be a good programmer in your own language. Each language only exposes certain concepts. Using other concepts in other languages lets you bring those patterns into your chosen language—albeit with greater difficultly. Without that knowledge you are more likely to just fumble through it rather than building something cleaner. Also relevant is the Sapir-Wharf hypothesis (http://en.wikipedia.org/wiki/Linguistic_relativity http://en.wikipedia.org/wiki/Linguistic_relativity). Language ultimately determines what you think.