Franklin suggests that romantic attachment can affect a person’s judgement. If Jack is in love with Jill, his perception of her beauty is shaped by affection, making him an interested rather than impartial observer. The saying uses physical attractiveness as a simple example of the broader way strong feelings can influence how people assess others.

The proverb does not mean that Jack’s admiration is false or that beauty can be measured entirely objectively. Rather, it draws attention to the limits of judgement when personal attachment is involved. Affection may emphasise qualities that an uninvolved observer would see differently or weigh less strongly. Franklin’s broader point is that people should recognise when their own emotions may be influencing an assessment. Personal experience remains meaningful, but it should not automatically be treated as neutral evidence about how something or someone will appear to others.