Perhaps I can make this a little more understandable. Suppose that for a month you were asked to guard an attaché case containing vital defense secrets.

You had to carry it with you every moment of the day—indeed, it was handcuffed to your left wrist. You felt endangered by its presence, of course, since enemy spies would go to any lengths to secure it.

Then, at last, the Marines and the F.B.I, arrived and relieved you of the burden. Imagine how good you'd feel!
But—wouldn't you also feel a little strange? Wouldn't you suddenly look around and wonder where the attaché case was, even two days later? Wouldn't your left wrist feel odd? Wouldn't many aspects of your day which had become "habitual" seem shockingly awry?

Cigarette smoking is something that has been "handcuffed" to you for considerably longer, I suspect, than a month.
It is not just one habit, but part of many habitual patterns.

ONE BIG REFLEX ACTION

A habit is a subconsciously controlled activity. When you do things habitually, you do them without conscious thought or conscious direction.
You don't have to do any purposeful thinking in order to light up a cigarette. It happens as automatically as the movements that enable you to walk up a flight of stairs. You smoke as naturally as you breathe.

All that is required to start you reaching for a cigarette and match is the appropriate impulse, and then your fingers, lips and lungs take over.
If you are ready to accept the fact that your entire smoking ritual is just as subconsciously controlled as such other daily activities as tieing shoe-laces or combing and brushing your hair, then you are ready to see why silly "substitutes" won't work and why will power can almost never accomplish more than temporary results.

Substitutes do not work because they
—do not "relax you" the way a cigarette relaxes you,

—and do not logically fit into your many "smoking patterns." In other words, chewing gum cannot be part of the pattern of getting dressed or reading your morning paper over a cup of coffee.
 

And will power doesn't work because it doesn't come up with anything that relaxes you or that supplies a logical substitute in your "smoking patterns."
But that's only part of the story.
"Will power" is conscious direction.

And when you set up a contest between conscious will power and subconscious habit, you create a conflict that results in mental anxieties and tensions. In this conflict, moreover, the subconscious and habit are almost always victorious.

In phobias, for example, there is usually "excessive fear of some particular type of object or situation; fear that is persistent and without sound grounds, or without grounds accepted as reasonable by the sufferer."* The sufferer doesn't accept his phobia as logical; he'd like to use will power—i.e., conscious direction of his mind—to escape its consequences; but he can't.

THE "POWER" OF WILL POWER ISN'T VERY POWERFUL AFTER ALL

The triumph of the subconscious over "will power" is not reserved, however, to the victims of phobias. You can test this fact for yourself. Your subconscious mind knows that failing is a bad thing. From early infancy it has done its best to prevent you from suffering bruising or frightening falls. At times you have been able "instinctively" to gain your balance when you might otherwise have flopped. That's been your subconscious at work.
* The italics are mine; the definition is from "A Comprehensive Dictionary of Psychological and Psychoanalytical Terms," English and English.
 

Now suppose you place a short, narrow plank of wood on the floor. Without any difficulty you walk on the plank and you walk the length of the plank.
But place that plank twenty feet off the floor, and you will find it hard to will yourself to walk its length. Your subconscious is there to stop what can lead to a fall. It keeps begging you and ordering you to stop this dangerous attempt. You inch and you crouch and you can scarcely get your legs to move.

Yes, and you know what your reaction would be if the plank were high in the air, between two tall buildings. You likely couldn't even step a foot onto it.

You may wonder how it is possible, then, for aerial-ists, steeplejacks or window washers to conquer their fears. Well, not one of them becomes an aerialist, steeplejack or window washer over night. It is a matter of gradually training the subconscious mind to accept heights, and thus to establish a habit pattern.

Will power cannot triumph over subconscious habit. Indeed, it has been found that will power and conscious attention is a considerable hindrance in the attempt to rid oneself of a habit.

If you play golf or dance expertly, you've probably noticed that the harder you try, the less likely you are to succeed. It's the relaxed, smooth player who scores. It's the relaxed dancer who quickly learns the new step, and follows it easily. Youngsters learn faster than adults simply because they have not yet gotten into the habit of consciously "trying."

WILL POWER CAN PREVENT SUCCESS

I began to see that will power is a highly overrated concept when I flipped through some of my reference books. In Dr. Matthew H. Chappel's book, "How to Control Worry," this line stood out: "Will power or effort, used to fight against or resist worry, is the very thing that perpetuates worry and keeps it going."