Eagerness Tempered by Reluctance

From Heart of Darkness:

Have you ever felt this way?

I have. Recently - actually - before reading Heart of Darkness, someone asked me what I had done this summer. I had done so many interesting things, and the day before I was literally rehearsing how exactly to encapsulate what I had done. Yet, when asked, I did not divulge everything I had done. Something restrained me. I wonder what this something was - was it self-consciousness? Modesty?

What exactly is this restraining force that tempers our eagerness that Konrad writes of and I (and presumably many others) have experienced?

I wanna eats the cookie, but it makes me fat :frowning: