Is life just driven by pleasure?

The more I thought about the true freedom of choice and the ability to truly do whatever we want, the more the thought crossed my mind; isn't it reasonable to believe that all of our actions and thoughts are subconsciously aimed to achieve pleasure? A simple counter point would be to look at a monk who isolates one self from any sort of pleasure. But I believe that the action of distancing from pleasure for the monk achieves a greater long-term form of pleasure. Every single thought and every single muscle contraction is done to achieve a greater form of pleasure. What if it is actually true that there is no way for an individual to preform an action lacking any pleasure whatsoever? I'm not claiming that this is true and would love to hear a good counter point