Happiness and Wikipedia.

Plato

To Plato the human soul consists of three parts: The reason, the will and the desire. A man is happy when all three parts of the soul are in balance.

Socrates

1. Keep interested in the truth.

2. Make sure that your soul is as good as possible. 

3. To get a good soul, maintain the four virtues of prudence, temperance, courage and justice (charity).

Epicurus

A life will be happy when we constantly train positive thinking. Epicurus called it "philosophize." A person should philosophize every day. One should think about the meaning of life and reflect again and again to his positive goals.

Aristippus

One who took a pride in extracting enjoyment from all circumstances of every kind, and in controlling adversity and prosperity alike. 

Two precepts

- "to endeavour to adapt circumstances to myself, not myself to circumstances" 

- "every complexion of life, every station and circumstance sat gracefully upon him." 

Thus when reproached for his love of bodily indulgences, he answered, that "it is not abstinence from pleasures that is best, but mastery over them without ever being worsted." When Dionysius, provoked at some of his remarks, ordered him to take the lowest place at table, he said, "You wish to dignify the seat."

Being once asked what advantage philosophers have, he replied, "Should all laws be repealed, we shall go on living as we do now."

Self Actualisation

It is the organism's master motive, the only real motive: "the tendency to actualize itself as fully as possible is the basic drive...the drive of self-actualization." -  Kurt Goldstein

- However, for Goldstein self-actualization cannot be understood as a kind of goal to be reached sometime in the future. At any moment the organism has the fundamental tendency to actualize all its capacities, its whole potential, as it is present in exactly that moment in exactly that situation in contact with the world under the given circumstances.

"the curative force in psychotherapy - man's tendency to actualize himself, to become his potentialities...to express and activate all the capacities of the organism." -  Carl Rogers

I think...

Animals are hedonists and we are animals. We have base instincts and drives that must be fulfilled. 

On the other hand we have mind and reason, which I believe aren't shaped by logic, but by circumstance. We should take the reigns of our monkey mind and steer out beliefs in a direction that aligns with our base desires. This follows Plato's notion of balancing reason, will and desire.

It seems to me that the crux of life's conflict is in negotiating between the internal and the external. I would say that the  main opposing schools of Greek philosophy align one with each. Hedonism would have one consider the pleasures of the external; Asceticism the contentment of the internal.

Extremes are rarely healthy in my experience, and I tend to trust the Buddha's middle way. The compromise that makes sense to me here is to follow our hedonistic desires while tempering the fallout with appropriate frames of mind. We should strive after what we want, but with a solid and impregnable core of self-worth, self-belief and satisfaction, and thus not be so easily swain by the winds of success and failure.

Whether this is my idealism wanting to have my cake and eat it too, only experience will tell.