"In the beginning God created the heavens and the earth" (Gen. 1:1).
If you have taken a science class, you know what it means to engage in scientific study. Whether the subject is chemistry, physics, or biology you seek to discover how things function. Such studies are called physical sciences because they involve analyses of the physical world. Many in the secular arena claim this is the only valid realm in which you can explore truth. Anything beyond the physical cannot be known, therefore inquiry into such things is futile.
Study of that which is beyond the physical is called metaphysics. Metaphysics deals not so much with the how of things, but the why. Studies that go beyond the senses are concerned with ultimate reality, that which causes things to happen and shapes things according to a purpose. Even though many claim we cannot know that which is beyond the physical, they make assumptions about unseen things all the time. Any scientist who forms a hypothesis does so because he is assuming certain realities based on some evidence (sometimes no evidence). He does not see what he is trying to prove but, in a sense, steps out on faith to prove that which he does not see.
The person engaged in metaphysics deals with two aspects of study: ontology and teleology. Ontology answers what a thing is, not what it does. It deals with the question of being. We see this concept fleshed out in the ontological argument for the existence of God. If we exist, there must be something that has always existed. This is because something cannot come out of nothing (not caused). The Big Bang theory says something suddenly exploded into being. This cannot be—something had to cause the explosion. How you think about existence and ultimate reality will have direct bearing on how you think about God, yourself, and your fellow creatures.
Metaphysics also deals with teleology. This is the study of ends, purposes, and goals. What is the purpose of our existence? God as the ultimate reality, has an ultimate purpose for what He does. Those who deny that there is a purpose behind everything that happens, that our destiny is shaped by an all-knowing, all-powerful being will respond differently in life than believers. Their understanding of the meaning of their own existence will be contrary to those who have their meaning and purpose rooted in God.
Like you did yesterday, today ask some people why they exist. Ask them how the universe was created. Ask them what gives meaning to their lives. Ask them how the theory of evolution brings meaning to our existence. Then ask them how God brings meaning to our existence. Ask them how we are to treat our fellow human beings, and why.