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Sustainability is no longer an option; it's a responsibility we owe to future generations.
The beauty of mathematics is that it allows us to abstract away the complexities of the real world and focus on the underlying principles.
To be aware of the idea of social structure and to use it with sensibility is to be capable of tracing such linkages among a great variety of milieux.
The best leaders are those who listen more than they speak and learn from everyone around them.