Quote by Critias of Athens
If you will discipline yourself to make your mind self-sufficient you will thereby be least vulnerable to injury from the outside.
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Summary
This quote suggests that by developing a self-reliant mindset, one can minimize the potential harm caused by external sources. By disciplining oneself to become mentally self-sufficient, individuals can reduce their dependence on external factors such as opinions, criticisms, or external circumstances. The idea is that a strong and independent mind is less vulnerable to the negative impacts of the outside world and can maintain inner stability and resilience.