Since the love of pleasure is natural to us all, why doesn't it lead to lasting fulfillment? The easy, and correct, answer is because pleasure doesn't last. When we are experiencing something pleasurable, we don't imagine that it will end, or even that there was ever a time without it. Then it invariably ends, and we are left empty handed, and the pleasure seeking begins again, and again, and again. (And we are left at least somewhat in pain from missing our pleasure.)
The more complex, and also correct, answer is that pleasure requires a subject/object relationship that is defined by cause and effect. Something or someone causes pleasure. Something gives us pleasure. We search for objects of pleasure, and then we search for more and different pleasure objects.
Pleasure breeds the desire for more pleasure, and objects of pleasure are many and varied. As we mature our pleasure searching usually matures with us, but remains essentially the same in form. We may no longer derive pleasure from playing with toys (children's toys, that is!), and maybe macaroni and cheese is not our ideal of a sublimely pleasurable meal, but we have found replacement objects. And these pleasure objects do give pleasure, but the pleasure is still temporary. The initial intense thrill has a short life, and so our seeking for new pleasure-giving objects is self perpetuating.
Unfortunately, yet perhaps naturally, people and their body parts become our pleasure objects. Certainly the mother's breast is an essential pleasure object, and one that informs pleasure seeking throughout most lifetimes. All advertising and marketing strategists exploit this obvious fact.
Our pleasure in feeling superior and powerful can lead to wars and allow the willingness that others be powerless in the midst of our plenty. The sensational love affair with pleasure has some dire outcomes for us all.
If pleasure led to fulfillment, our society would be an exemplar of fulfillment. We are bombarded with known pleasure objects throughout our day, and all it leads to is more pleasure seeking and less fulfillment.
Yet there is nothing inherently wrong with pleasure! Many pleasures cause no harm to anyone, and even contribute to the over all atmosphere of well-being. The problem only arises when pleasure (and always more pleasure!) is believed to ultimately deliver lasting happiness or fulfillment, or when pleasure is the central reference point for the life of an individual or a society.
Fulfillment, however, doesn't depend on subject/object and cause and effect relationships. Fulfillment exists in a different realm, a realm out of the reach of the pleasure/pain dichotomy. Fulfillment is deeply pleasurable in itself, but it is a pleasure that doesn't depend on any object for its life.
We already know fulfillment in certain arenas. We can be fulfilled in playing a game whether we win or lose (even if we play hard to win and feel pain in losing.) We can be fulfilled in our work whether it is stressful or not and whether we are acknowledged or not (even though we may wish the stress were less and want acknowledgment.) In fulfillment there is room for all sensations including pain.
Fulfillment is the natural result of realizing peace at the core of your being. Peace in the core of you needs nothing and is present in all circumstances. In a moment of willingness to open to that peace rather than to continue the search for pleasure, fulfillment can be realized.
When this choice is actually present in your daily life, you can notice how the habit, or even addiction, of seeking more pleasure causes you to ignore the fulfillment that is natural to you. When you recognize inner peace, you revel in pleasure when it is present, even grieve a bit at its passing, and still realize your essential unchanging fulfillment.
This brings us to the essential question of this post: Do you want pleasure or do you want fulfillment for your life?
When fulfillment is wanted, then pleasure for its own sake is not the reference point for any particular action, and there are many other questions and reference points, such as:
Does this particular pleasure cause harm to someone?
Does this pleasure demean myself or another?
Is this pleasure in alignment with what my life stands for?
I am sure you can significantly add to this list, and I invite you to do so.