One of the central aspects the the theme of Lost is the idea of competing ideals within a community, and how to accommodate your own desires and beliefs with those of "others". One of these ideas at the forefront is the idea of Science vs. Faith, and in particular how it applies to the characters of Jack Shephard and John Locke.
This idea has been permanently attached to these characters since the moment where they decide what they are going to do about the button on the Swan Station computer. These two men get labeled from this moment on as either men of science or faith. I don't believe it is as easy as that to label someone as being only one type of person in any regard.
So we have to ask ourselves: does Jack have "faith"? and is Locke motivated by "science"?
We are unsure of Jack's religious affiliation, and in my opinion, religion and faith don't have to mean the same thing. In most cases Jack's faith is in question regarding the supernatural phenomena occurring on the Island. However, Jack does experience supernatural phenomena. So it's not a question of faith necessarily. Jack's concern is more focused. He sees his dead father on and off the Island. His thought is that he is losing his mind. A very rational question to ask himself. He knows that he is seeing his father. There is no lack of faith there. It's just a matter of whether it is something that he can control or not. Further, crazy and dangerous things happen on the Island that are very supernatural in origin. There is a giant monster made of smoke that has attacked his people. Jack knows it is real. There's no question of faith here. He is more concerned whether it is a threat to him, and whether he has the ability to protect his people.
I would also say that Jack does have tremendous faith in other respects. When he makes a decision, he becomes blinded by his determination to see it though. He had faith that he would get his people rescued. He had faith that the individuals on the freighter were there to rescue them. Now, we know he was mistaken, and we could say that he had "bad faith" in these cases. However, it does not take away from the fact that he had faith and it was very strong. He didn't think that God was going to save them, but that does not reflect his level of faith that they would be saved.
John was the one who described this model to Jack in the first place. John is a self-professed man of faith. However, we see John struggle to no end to find a purpose and to follow his faith. After discovery of the Pearl station, John's faith and dedication to the Island is forsaken. His fears of being manipulated cause him to lash out and doubt himself. He later admits that he was wrong, and chooses to lean on his faith to help him survive and thrive on the Island.
So what does he mean when he says "man of science"? What is the scientific approach to surviving on the Island? and does John exhibit these characteristics. By "science" we may mean to say "rational decision making". I would argue that every survivor would have to make rational decisions every day, and that it would not compete with any amount of faith that they may have. We could mean "experiencing with our senses" or "observable evidence based assumptions". There is no escaping either of these methods of understanding things.
Much of John's focus on the Island is the accumulation of knowledge. He wants proof that something spiritual is happening. He may "feel" it, but he needs to know. This is a very scientific way of approaching things. He accepts that the Island has a plan for him, but he won't just sit back and wait to figure out what it is. He is a seeker. He asks questions, digs up truths, and takes control of his own destiny. Does that sound like pure faith?
During the Time Flashes, John experiences several events on the Island that he interprets as guidance toward the Island's plan for him. Does he jump at the first one? No! It takes several miraculous events to inspire him to take up the mantle and leave the Island. He sees the crash of the Beechcraft (where his sidekick Boone was killed trying to participate in John's journey of faith), he meets Richard (twice in two different decades), he revisits the night of Boone's death and the moment when all his hope had vanished only to be saved by Desmond (who was having a similar crisis of faith at the exact moment). Then people started dying, and John finally decided that he understood the Island's plan. He didn't take it on blind faith from Richard. He had to work it out logically. Was the Island guiding him to leave? What do all these signs mean? Will the plan work? etc.
Seasons 1 2 and 3
While there were plenty of reasons for them not to get along, the final weigh in on the Science/Faith dispute lies in the fact that John believes that the Island itself has a purpose for the survivors, and Jack believes it was all a coincidental accident. We don't know who is right or wrong. Maybe neither, maybe both. They have every right to their opinions, but neither side of the argument is driven solely by science or faith.
John has faith that there is a purpose to the plane crashing on this particular Island. However, it's not driven purely by faith. John survived a plane crash and was cured of his paraplegia. These are miraculous events to be sure! But are we seeing a purely faith based assumption? He doesn't need to have faith about curing his paraplegia. He's walking around. That's evidence-based science. Something happened, and John attributed it to a source. His faith lies in the fact that the Island wanted him healed for some divine purpose.
So it's a combination of the two.
Jack didn't want to push the button in the Hatch. He thought it was stupid to blindly trust some crazy man with a computer. But he pushed the button. Maybe he was inspired by the fact that this crazy Scot was the same someone who he had had a discussion with years before regarding miracles. (After which Jack experienced a profound miracle with Sarah's recovery from a spinal injury.) We could look at it from the scientific angle, too. It's simple mathematics. The odds of everyone blowing up by pressing the button are potentially worse than the odds of blowing everyone up by not pressing the button based on the scientific assumption that someone had been pushing the button and nothing happened. Whether or not there was a real threat could not be known to Jack. He could have been playing the odds. Playing the odds is a faith-based decision, even if it is backed up by good science. Rolling a 7 on a pair of dice has tremendous odds in your favor, but there is always the chance that you could roll another number. Your faith in mathematical odds is what makes a game like Craps fun, and knowing the odds can make you rich. It's a win/win. (Unless you suck at Craps like I do. Then all you will do is lose/lose.) Another semi-scientific rationale could be the threat that it caused to the cohesion of the survivors. It was a social threat, if not only a physical threat. Jack knew, logically, that this issue could divide them. It was a rational decision to push the button, even if it was just to pacify John Locke. But his faith in the group guided this decision.
Again, a combination of the two.
So my thought is that both men are motivated by Science and Faith. They may disagree with their purpose, but neither accepts their lots lying down. They have faith in themselves, but all the while their decisions are governed by their experiences.
Ben is a great example of science and faith working together. He has faith in the Island. He follows Jacob and Richard's instructions. He is confronted with obstacles to his faith, but he looks for guidance, and he shows his appreciation to the Island.
But he is cold and calculating. He is the most rationally minded person on the Island. He knows that blind faith will get you face down in a ditch. You have to take control of your destiny as well as heed to the Island's wishes.
Ben is not a role model by any means. The point of the example is to show that the two sides do not conflict for him. He may be a maniac, but he is a happy maniac.
Seasons 4 5 and 6
The first three seasons showed us the importance of science and faith in the lives of our two central heroes. In Seasons 4 and 5 (and presumably 6), we see what happens when the two concepts are out of sync, and we watch the lives of these characters come crumbling apart.
Jack had faith that leaving the Island was his destiny. He would never say that, but I would argue that it is pretty obvious to the viewer. It turned out that his rejection of John Locke and his inability to have faith in the Island contributed directly to his downfall afterward.
John had total faith in the Island from the moment he woke up on the beach 5 years ago. It was his faith in the Island that drove him to fulfill MIB's mission for him to leave the Island. His faith got him killed. Had he dug deeper into the mystery, he would not have been so quick to trust Christian Shephard in the absence of Jacob. He was impatient, and easy to manipulate by Christian and MIB.
Now Jack is driven by faith. He sees a purpose for him laid out by the Island. But it involves science. Daniel Faraday was a scientist, and the theory that has driven Jack to launch a bomb into a deep chasm (and pray that it doesn't kill everyone) is based on Daniel's lifetime of scientific research and experimentation.
Jack sees the balance. He can't be ignorant to one side of the argument anymore. Without Daniel's science, there is no faith in the plan working.
What's in store for John Locke? I propose something similar will take place this year. His story is far from over. His faith has lead to this terrible turn of events with a Villain coming on the scene and manipulating everyone using John's good name. It's despicable. So how will this turn around. Is John's faith in his mission part of Jacob's endgame? Jacob's enemy used John's faith against him, but will Jacob pull a super-sneaky bag over his head?
Could John's faith in the Island save them all? Not without a cold, calculated, scientific, evidence-based plan.... and a dash of faith in John Locke himself.
As with most competing ideas, the truth lies in the middle. Faith and science work together in almost every decision and action. One begets the other in many cases as well.
If someone was creating a scientific experiment they would have faith that it would produce the outcome that they desire. They would have faith in their abilities and their purpose. However, they would use strict rules of science to govern which types of outcomes they will accept and how they go about achieving them.
Likewise, a very religious individual has faith that their God is guiding them and has a purpose for them. However, they turn to their individual religious texts and their friends in the religious community to "compare notes" on their experiences. Religious texts provide guidelines that aim to give an experience-based structure to spiritual quandaries. In addition, one may have faith that God is guiding them, but many faith-driven individuals look for miracles and point to evidence in their own lives of God's presence. For no other reason than to strengthen their existing faith.
Certain sides are stronger for certain individuals. Our experiences dictate how we interpret the world, and what guides us and provides for our survival. However, the lesson we should take from the lives of Jack and John is that forsaking faith leads to bad science, and distrusting science and logic creates bad faith.