Finally she said desperately, 'Captain Thiel, how is it pos-
sible for a body to change as much from one ego-shift to an-
other as it does between Susan and me?'
'There isn't all the change you imagine,' he said. 'Have
you had your first physiology?'
'Yes. I was very good...' Mary saw from his smile that
her inadvertent little conceit had trapped her.
'Then, Miss Mary Walden, how do
ble?'
Why did teachers and medicops have to be this way?
When all you wanted was to have them talk to you, they
turned everything around and made you think.
She quoted unhappily from her schoolbook, 'The main
things in an ego-shift are the two vegetative nervous systems
that translate the conditions of either personality to the blood
and other organs right from the brain. The vegetative nervous
systems change the rate at which the liver burns or stores
sugar and the rate at which the kidneys excrete...'
Through the closed door to the other room, Mrs. Harris's
voice raised at the visiophone said distinctly,
'Reabsorb,' corrected Captain Thiel.
'What?' She didn't know what to listen tothe medicop
or the distant voice of Mrs. Harris.
'It's better to think of the kidneys as reabsorbing salts
and nutrients from the filtrated blood.'
'Oh.'
'What about the pituitary gland that's attached to the brain
and controls all the other glands during the shift of egos?'
pressed Captain Thiel distractingly.