Reasoning

Reasoning

Reasoning moves from premises to a conclusion. An argument makes that move explicit so we can examine whether the conclusion follows. You may come to the immediate conclusion that “I have to take Main St. to work today” from the claims, “There are only two ways for me to get to work, either Highway 1 or Main St.” and “Highway 1 is closed due to construction.” In argument form, this piece of reasoning looks like the following:

1. There are only two ways for me to get to work – either Highway 1 or Main St.
2. Highway 1 is closed due to construction.
3. I have to take Main St. to get to work today.

Given those premises about Highway 1 and Main St., the conclusion follows. The next example uses a general statement and a particular case:

1. Politicians in the Crack Down Party are all conservative about spending.
2. Congresswoman Smith is in the Crack Down Party.
3. Congresswoman Smith is conservative about spending.

If both premises are true, the conclusion about Congresswoman Smith follows.

Now, let’s say you’re watching your favorite courtroom drama on TV and the attorney for the defendant puts forward this argument:

1. If my client committed the crime, then he would have been in Chicago.
2. But he was not in Chicago; check the gas receipts, GPS, and witness testimony.
3. Therefore, my client did not commit the crime.

If both premises are true, the conclusion follows: the defendant did not commit the crime.

Sometimes, we are confronted with claims that require us to reason through their connections slowly, in a more conscious fashion. Consider a certain apartment lease agreement. Let’s say that you got a new job in Denver, Colorado, six months into a 12‐month lease agreement you signed with an apartment in San Francisco, California, so you need to move from your apartment and would like to break your lease. The contract states:

The lessee may be let out of the 12‐month lease agreement if and only if:

1. He can find another lessee to take his place for the remainder of the agreement;
2. or He is moving out of the state for work purposes only.

However, if (1), then the new lessee (the one replacing the lessee who broke his lease agreement) must sign an additional 12‐month lease agreement. If (2), then the lessee must provide a notarized copy of the offer of employment. If neither of these conditions can be met, then the lessee will not be let out of the 12‐month lease agreement.

Since you have a notarized copy of your offer of employment for the job in Denver, Colorado, you reason correctly that you, the lessee, will be let out of your 12‐month lease agreement.