Being thin is dangerous
A soothsayer calls out to Caesar as he passes and warns him against the ides of March, March 15. Caesar ignores the man and dismisses him as a dreamer. Upon seeing Cassius, Caesar informs Antony that he would rather be surrounded by men who are fat and happy than thin men like Cassius. He is worried that Cassius is dangerous because he "thinks too much" (1.2.193-196). Antony tells him not to worry about Cassius.