[thatsethnz]

But you have to teach altruism, cooperation and the valuing of other people. And you teach it by (gently and respectfully) disincentivizing the opposing behaviors.

It's not "be helpful or be punished" it's "don't pour your cereal on your brothers head or you will get time out", "don't wake your brother when he's sleeping or you will get time out" "stop biting your bother or you will get time out", "no you cannot wear your new shoes in the mud and if you don't stop asking and complaining you will get time out". These are the bread-and-butter conversations of parenting.

Like it or not, you will be a valid authority in your child's life, and you will need to teach compliance with proper authority, and model how to be one, and that there are consequences to the defiance of proper authority.

[tpxl]

There is significant difference between punishing absence of good behaviour ("be helpful or be punished" - Henry example) and punishing bad behaviour ("don't pour your cereal on your brothers head or you will get time out" - your child example).