Willpower

Of all the mind's abilities the ability to make rational decisions and follow through with them is possibly the most specific to humans. Animals can feel, and to some level even think, but their ability to decide what behavior to follow is quite limited or simply does not exist, and it is always condioned by hereditary behaviors ( instincts) and hormones.

On the other hand the human being has been given the ability to decide freely, above all hereditary, instinctive or hormonal conditioning; and thanks to will power, decide to follow the most healthful behavior, despite what sounds good or what one likes.