See the little red X? If you ever don't want to complete a Whim, or want a different one, simply click that X, and it goes away. Let's look at Aspirations a bit! Click the big star icon in the bottom right. This tells you what your current Aspiration is, your level of Satisfaction and current goals for your milestone.
You’ll also find buttons to change your Aspiration and buy rewards. If you hover over the big gold button inside the Hexagon, you'll see your current Milestone and the Reward Trait you’ll receive after completing the Aspiration.
If you hover over the goals, you'll see detailed information on how to complete it and how much Satisfaction you'll receive.