"You and I are no more than biological machines, organisms built by DNA for the sole purpose of passing it on. Just as the universe is comprised only of matter, we, too, are purely physical objects." This view is called naturalism, a view that has come into prominence because of the successful pursuits of modern science.
Naturalism tells us that nothing exists beyond the physical realm. If we cannot measure it, see it, or touch it – it does not exist. By following the scientific method, we have discovered the laws of physics, the descriptions of how our physical universe normally and consistently behaves. But according to naturalism, mankind is no different than its habitat. Since the universe obeys the laws of physics, we, too, are wholly subject to them.
You may have thought that a series of free choices has led you to where you are today. But according to naturalism, free will does not exist. Since human beings are merely physical entities, we are bound by the laws of cause and effect. Our actions today can be traced back to prior physical causes. In turn, these causes can be traced all the way back to the beginning of the universe. The result? All of your actions – past, present and future, have been predetermined since the universe began.
Fortunately, determinism itself is not an inevitable conclusion...