The phrase implies that with knowledge or education one's potential or abilities in life will certainly increase. Having and sharing knowledge is widely recognised as the basis for improving one's reputation and influence, thus power. This phrase may also be used as a justification for a reluctance to share information when a person believes that withholding knowledge can deliver to that person some form of advantage. Another interpretation is that the only true power is knowledge, as everything (including any achievement) is derived from it.
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