Question

Explain how Juliet comes to her decision at the end of her soliloquy. Are her reasons based more on logic or emotion? Support your response with evidence from the text.
JULIET: Farewell! God knows when we shall meet again.
I have a faint cold fear thrills through my veins,
That almost freezes up the heat of life:
I'll call them back again to comfort me:
Nurse! What should she do here?
My dismal scene I needs must act alone.
Come, vial.
What if this mixture do not work at all?
Shall I be married then to-morrow morning?
No, no: this shall forbid it: lie thou there.
[Laying down her dagger]
What if it be a poison, which the friar
Subtly hath minister'd to have me dead,
Lest in this marriage he should be dishonour'd,
Because he married me before to Romeo?
I fear it is: and yet, methinks, it should not,
For he hath still been tried a holy man.
How if, when I am laid into the tomb,
I wake before the time that Romeo
Come to redeem me? there's a fearful point!
Shall I not, then, be stifled in the vault,
To whose foul mouth no healthsome air breathes in,
And there die strangled ere my Romeo comes?
Or, if I live, is it not very like,
The horrible conceit of death and night,
Together with the terror of the place,—
As in a vault, an ancient receptacle,
Where, for these many hundred years, the bones
Of all my buried ancestors are packed:
Where bloody Tybalt, yet but green in earth,
Lies festering in his shroud; where, as they say,
At some hours in the night spirits resort;—
Alack, alack, is it not like that I,
So early waking, what with loathsome smells,
And shrieks like mandrakes' torn out of the earth,
That living mortals, hearing them, run mad:—
O, if I wake, shall I not be distraught,
Environed with all these hideous fears?
And madly play with my forefather's joints?
And pluck the mangled Tybalt from his shroud?
And, in this rage, with some great kinsman's bone,
As with a club, dash out my desperate brains?
O, look! methinks I see my cousin's ghost
Seeking out Romeo, that did spit his body
Upon a rapier's point: stay, Tybalt, stay!
Romeo, I come! this do I drink to thee.

Answer 1

The answer would be that Juliet's reasons are based more on her emotions, rather than logic. To support this statement in the play Romeo and Juliet, Juliet says, "I have a faint cold fear thrills through my veins,
That almost freezes up the heat of life:
I'll call them back again to comfort me:
Nurse! What should she do here?
My dismal scene I needs must act alone.
Come, vial.
What if this mixture do not work at all?
Shall I be married then to-morrow morning?" 
This shows that she is panicking about using the vial. She is constantly questioning herself because of her panicked emotions. 

Answer 2

Juliet uses both logic and emotion to make her decision, but her emotions ultimately help her decide. She struggles with many internal fears as she builds up her nerve to take the potion that Friar Laurence has given her. She feels that her family has betrayed her by forcing her to marry Count Paris. She feels bad about lying to her family and going against them and wishes that things could go back to the way they were.

After she realizes she must be mature and make this decision by herself, Juliet has to overcome her fears about the potion. She briefly doubts Friar Laurence, but immediately reminds herself that he is a holy man and that she can trust him:

I fear it is: and yet, methinks, it should not,

For he hath still been tried a holy man.

Since the potion is alien to her, Juliet doesn’t know if it’ll work properly. She’s worried about what will happen if she wakes up before Romeo arrives to save her and she suffocates and dies in the tomb:

Shall I not, then, be stifled in the vault,

To whose foul mouth no healthsome air breathes in,

And there die strangled ere my Romeo comes?

Despite all her fears, when Juliet imagines that Tybalt’s ghost will try to kill Romeo for revenge, she makes up her mind to drink the potion and hope that everything works out with Romeo. In the end, it’s clear that Juliet’s love for Romeo helps her to overcome her fears and to make her decision to drink the potion.