What the title is suggesting is: why as a result of living in a purely scientific world we need god.
Before we carry on we must get on the same page, then the dilemma will arise.
Do you believe in free will? remember your answer.

When you throw a ball if you where to know the speed of how it was thrown and how strong the wind is and all the other factors you would know where it is going to land. Our brains are also part of the physical world. When we make choice, if someone where to know every neuron in our brain she would be able to see what we're going to eat at breakfast. Know imagine she is omniscient. If she knew everything about everything then she would be able to know what is going to happen in the next second. And on this point she would still know everything about everything and would be able to know everything in the second there after. And if this were done infinity she would know everything about the future. So we can deduce that she would know exactly how your life is going to be and she would know exactly what choices and actions you make. You could do nothing to break this cycle as you and I adhere to the laws of nature. Even if you tried to make you're choices by doing something random she would know what your method of randomness is and with enough information nothing is random (as an example you can a random number generator or coin flip can be calculated) so she would know what choice you would make.
Now my point is. You have no free will. You can do nothing to escape this completely scientific fact (this isn't pseudoscience like ID and etc...). So if I were to torture and gut seven people tomorrow (just a grotesque example to embolden my point) it wouldn't be wrong because I didn't have a choice. Hitler couldn't have been evil because he didn't even have a choice in doing what he did and thinking what he thought.

The only way this cycle isn't true is if there is something over-human (something supernatural that doesn't adhere to the laws of science).