Conservative vs. Liberal Logic: A Comparison

Martin Cothran | March 14, 2017

If you read the news or follow politics, you hear a lot of arguments and all of them sound different.

But in reality, there are only two basic ways to argue. We could call these two kinds of argument "Arguing Forward" and "Arguing Backward."

Arguing Forward is principled in nature. It involves beginning with a principle or a universal truth and inferring a conclusion that is its consequence. Abraham Lincoln is a good example of someone who argued forward.

On the issue of slavery, Lincoln began with the assumption that no human being should be enslaved. That was his broad, general principle. He then employed the specific assertion that Blacks were human beings, from which it followed that No Black person should be enslaved:

1) If no human being should be enslaved, then Blacks should not be enslaved.
2) No human being should be enslaved.
3) Therefore, Blacks should not be enslaved.

This kind of argumentation is similar to that used in geometrical proofs. In fact, along with the King James Bible and the plays of Shakespeare, Lincoln carried around with him a copy of Elements, Euclid's ancient treatise on geometry. He even appealed to Euclid's principle of geometrical equality in his case against slavery.

Arguing Backward, on the other hand, involves beginning with particular cases and arguing backward from these to some principle or policy. In the debate over abortion, for example, advocates of abortion argue that, since outlawing abortion would result in more deaths from "back-alley" abortions, abortion should remain legal.

Here are the steps of the argument:

1) If abortion were outlawed, there would be more deaths from "back-alley" abortions.
2) We should be against any policy that results in more deaths from "back-alley" abortions.
3) Therefore, we should not outlaw abortion.

This argument attacks an asserted consequence of anti-abortion policies and then argues backward to deny the legitimacy of the thing that would bring these consequences about. It is consequentialist in its nature.

Traditionally, conservatives have mostly argued forward, from principle, and liberals mostly backward, from consequence. In fact, the abortion debate is a good example of this. While liberals argue backward from the consequences of abortion laws to their undesirability, conservatives argue forward from the principle that a fetus is a human being to the need for pro-life laws.

Here are the steps of the conservative argument against abortion:

1) If abortion takes the life of an innocent human being, then it should be outlawed.
2) Abortion takes the life of an innocent human being.
3) Therefore, it should be outlawed.

This argument affirms a principle (no taking of innocent human life) and goes forward to infer a consequence.

However, both sides in political debates can use both kinds of argument. And, in fact, modern conservatives, as they move further away from traditional-values issues which involve the application of eternal principles (such as the sanctity of life and marriage), are now as consequence-based in their reasoning as liberals. And liberals, as they have taken up what they believe to be universal principles (equality, tolerance, diversity), are becoming more principle-based in their argumentation.