These were the words of a wise man.
Weeds are unwanted plants. This analogy, typifies the human nature. Seeds are good traits -when inculcated, form a bedrock of values that define an individual, the quality of his/her life and the way the impact the society. Weeds, as in the case of seeds, are sown but in most cases, UNINTENTIONALLY. Bad character traits, may go unnoticed for a while but would always surface when tempers flare or when there is need for self-control.
Good behaviour(seeds), is born out of an INTENTIONAL decision to act right. This decision, in effect, informs an individual's action. You clearly choose what you become, by what you allow into your mind.