We have already established that man is an animal. For any given animalistic existence, the three components of food, sex and danger constitute the essential triad. Sex is the key to biological immortality - living the afterlife in offspring. It's the most peaceful, non-violent and beautiful protest in the face of death. Remember the beauty of Hegel’s philosophy - the absolute is neither - being nor non-being, rather it's becoming. For all our earthly materialistic purposes, sex is absolute for it is the process of biological becoming. It's the axis around which our being revolves, it's the centre of the circle of life. To quote Woody Allen - “I don't know the question, but sex is definitely the answer.”
Food provides daily nourishment to the body and thus extends life every moment after moment. Danger can threaten existence. Fetching regular food and evading persistent danger increases the chances of copulation. In nutshell, food extends our mortality, sex ensues biological continuity and evading danger secures life. Man in its animalistic form is restricted by these essential triads for sustenance.
The trinity of food, sex and danger is so important that a large part of the brain is devoted to this purpose. In the psychological domain, it is often referred to as the old brain, or reptilian brain as we share this portion with almost all the animal kingdom. Our animalistic instincts cannot afford to miss any opportunity of the possibility of either of these elements of the essential triad. Probably, this is also the reason that the economy of the advertisement industry revolves around it. To sell cosmetics to underwear, we use sex. The food industry is booming due to the sheer essentiality of food. When nothing works, the danger is the perfect recourse, building empires in the insurance sector. The triad never fails to make sales. Most successful commercials use these basic psychological and physiological needs in their favour.
Since we share body and soul with the animal world, we are bound by the limitations of the essential triad. But as rational men, bestowed with the power of creativity, we have something more to our existence than just physical presence and basic survival. Throughout evolution, our brain functioned not only like an organ to control the basic reflex mechanism of the body. The brain also houses the faculty of emotions, modes of communication in the form of languages, understanding of literature, the ability to discover, invent and innovate - the sciences and the arts. The brain grants its limited space to the infinity of the mind - the most powerful tool known to date.