children, by the exercise of their senses about objects that affect them in the womb receive some few ideas before they are born, as the unavoidable effects, either of the bodies that environ them, or else of those wants or diseases they suffer; amongst which (if one may conjecture concerning things not very capable of examination) I think the ideas of hunger and warmth are two: which probably are some of the first that children have, and which they scarce ever part with again.