Question

why did calpurnia try to prevent caesar from going to the senate house

Answer 1

Calpurina got some predictions that ceaser end was near as she got bad dreams in night like blood lying on capitol and people washing their hands in blood and lioness gave birth to cubs in street and huge thunder so calpurnia prevents ceaser not to go to senate house

Answer 2

She had stopped Caesar from going to the senate house because she had a bad dream that day. According to her dream, a lioness gave birth to its young one in the street, his(Caesar) blood was flowing all over the streets, everyone were bathing their hands with the blood of Caesar, there was a fight taking place in the clouds. Usually, she would not believe in such supernatural elements. But that dream was too bad. This was the reason she stopped Caesar from going to the senate house.
She did not succeed in her attempts as Brutus justified the confusion made by Calpurnia. He had interpreted them in a different way.

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