Dukkha universal truth suffering cause craving overcoming Nirvana Four Noble Truths Wheel of Life Anicca Anatta Dukkha Three Marks of Existence impermanence non-self Buddhist worldview Five Precepts moral discipline non-harming stealing sexual misconduct false speech intoxication Family spiritual growth moral support Right Livelihood compassion loving-kindness Buddhist upbringing Contraception intention non-harming Right Intention precepts family planning dependent origination Marriage companionship lay precepts social harmony emotional support Buddhist ethics