Those who hold that all that exists is matter and energy ultimately must maintain that everything is explained through physics and chemistry and that there is no ultimate cause or purpose in the universe. Things are the way they are because of a long series of chance occurrences. Cornelius Van Til is quoted as having said the following in relation to the materialists view of chance:
If you have a bottomless sea of Chance, and if you, as an individual, are but a bit of chance, by chance distinguished from other bits of chance, and if the law of contradiction has by chance grown within you, the imposition of this law on your environment is, granted it could take place, a perfectly futile activity.
What Van Til is saying is that to the one who denies the existence of God, the only option left is that things are the way they are because of chance, and that there is no purpose in the universe. Even such basic principles as the law of contradiction (sometimes called law of noncontradiction) cannot be trusted, for it too arose in our minds due to chance.
It gets worse. In a purely materialist universe, the mind that holds meaning is at best an emergent property, in the same way electromagnetism is an emergent property. Pure materialists hold that mind is an illusion, and all we really have are brain functions, which again arose by chance. So to the materialist, meaning is at best an illusion, a chance occurrence similar to seeing pictures in the clouds. We cannot even apply basic reason to the world, for such things as the law of noncontradiction only occurred to us by chance. In fact, all of what we know in the world is the way it is but by randomness, which could be otherwise. Van Til’s comment was to include all knowledge in this doubt.
However, chance is a bit of a misnomer. Nothing truly happens by chance, for chance is not a causal force. Chance is but an explanation of an effect. If a man rolls a pair of dice, the numbers are said to arise by chance, but this not true. The numbers arise due to the force applied by the man, the angle he releases them, the force he applies, the surface friction on the table, air pressure in the room, and other factors. So chance is not a causal force, and philosophically-inclined materialists are forced to use the phrase “causally closed” indicating that all events in the world are not chance, but one big endless series of causes. One can imagine some sort of endless series of dominoes, knocking each other over, round and round in endless circles.
But regardless of the existence of chance or causal closedness, the materialist is locked into a world without meaning, without purpose, without any true end in mind. Our illusion of consciousness arises, lasts for a while, then disappears.
Christians, however, have an ultimate goal, a loving relationship with each other and with a loving God. We can have the peace of knowing relationships with our loved ones will last, and our existence has meaning and purpose. In the end, love wins out over all.