The only science worth studying is the science of life. For all the other subjects you touch on, all the other activities you undertake, will only really bring you something if you focus on this one essential reality: life.
So, instead of using it to satisfy your desires, ambitions, and whims, learn how to regard life as a goal, and employ all your faculties to reinforce, enlighten and purify it within you, because without life, you have nothing else.
Your intellect, your heart and your will are all nourished by life.
When you sustain this life in you, your intellect understands, your heart loves and rejoices, and your will is reinforced and creates. Without life, even knowledge is impossible, and there is no more philosophy, no more religion and no more art.
This is why the science of life is the key to all realisations.