This is an ABC podcast.

One of the best bits of having a baby for me has been all of the glorious cuddles.

Oh my gosh, it's heaven.

And for the first eight months of my son's life, he would only nap in the

carrier, hanging off either myself or my husband, his sweet little head resting on our chest,

which was lovely, but also a nightmare, depending on the day you asked us. But I digress,

the point is, we were trying to provide our baby

with a sense of safety and love

and we were responding to his needs.

But a hundred years ago,

we would have been told

we were terrible parents for doing this,

that we were ruining him,

destroying his future.

And when you go back into the psychology books of the early 20th century,

you find that the word loved actually is not in them.

If you go into the index there,

the term they use for the relationship between mother and child is proximity.

Deborah Bloom is a Pulitzer Prize-winning science writer and director of the Knight Science

Journalism Program at MIT in Cambridge, Massachusetts.

And the way they define the relationship is a series of drive reduction formulas.

The child has a drive to eat.

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