Marcus Brutus has many admirable qualities. He is forthright, honest, sensitive, and intelligent. On the other hand, Brutus also displays character flaws that create problems for the assassins. In Act II, Scene i, Julius Caesar by William Shakespeare, Brutus makes his decision after much contemplation and inner turmoil. In his soliloquy in his garden, Brutus explains his decision.
The scene takes place early in the morning on the Ides of March. Brutus talks through his decision to join the conspiracy.
Brutus begins by saying that he has no personal problems with Caesar. [Unlike Cassius, Brutus has been a friend of Caesar.] His concerns are for the welfare of the Roman citizens. Caesar wants to be crowned emperor of Rome. Brutus wonders what how that would change Caesar.
Brutus gives an analogy:
He compares Caesar to a poisonous snake that one might encounter in the day. The smart person would avoid the snake. If Caesar is crowned, he might become like the snake, poisonous. Caesar could misuse his power. He might no longer have compassion for the people if he gains too much authority. Brutus admits that he has never seen that side of Caesar. He seems always the same and and his not usually swayed in this thinking by his emotions.
Brutus uses a second analogy:
When a person is at the bottom of the ladder of success, he turns his face toward the top and works to climb the ladder. However, when he achieves the top most rung of the ladder, the person might turn his back on those who helped him along the way. He may look to the heavens rather than those who are beneath him.
Caesar might do this. He could forget those who have helped him in the senate.
If this is a possibility, then it must be prevented. There is the argument. He is not at that stage, but if he is given power, he might.
Brutus uses the third analogy:
And therefore think him as a serpent’s egg
Which hatch’d would as his kind grow mischievous,
And kill him in the shell.
He compares Caesar to a snake in the egg. If it hatches, there is a chance that it might sting someone. So before the snake hatches, kill it in the egg.
Brutus has made his decision. Kill Caesar for the things that he might do. He does not know of anything that Caesar has done yet. To prevent the possibility of Caesar becoming too powerful, kill him before he misuses his power.
As soon as he has made his decision, the conspirators come to make sure that Brutus is joining them. Everything is in place for the assassination to take place on this day.