From the Unix Philosophy Page

.. When your tools shape your work, you feel friction instantly and you fix it.

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.. Constraint is not a hardship. It is a design instrument.

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.. Iteration is the real productivity engine. When you can change something and see the result quickly, you learn what works.

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Keep the system small enough to understand.

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Let programs stay replaceable. The future you can't predict arrives anyway. Parts that can be swapped out survice change.