Lewis Carroll emphasizes the importance of integrity and consistency in one’s life. The principle suggests that one should only choose to live in circumstances where they feel willing to face the ultimate sacrifice—death—if necessary, highlighting the significance of living authentically and truthfully.
He underscores that true safety comes from aligning one’s lifestyle with their deepest values and convictions. Living in a way that you'd be unwilling to die for implies a lack of sincerity or moral harmony, making such a situation unsafe and unstable.