Rule #2: You Cannot Spoil a Baby

Likewise, you cannot "train" a baby. 

Infants cry because they have needs.  They physically need to be held and loved, because their brains cannot yet distinguish between want and need.  Ignoring a baby's pleas causes stress and physical pain.  "Crying it out" does not teach a baby to be self-reliant; it teaches him to be insecure.