Only trust thyself, and another shall not betray thee.

The line counsels radical self-reliance: if you anchor your safety and integrity in your own judgment and conduct, you reduce the power others have to harm you through deceit or broken promises. Read this way, “betrayal” is less a claim that other people will become trustworthy and more a reminder that disappointment often follows from misplaced dependence—expecting others to secure what only one’s own prudence, boundaries, and moral steadiness can secure. The archaic “thyself” frames the advice as proverbial wisdom, aligning with early modern moral maxims that emphasize inward governance over external assurances.