In the first two sentences, the author observes that scientific claims are similar to myths in that they try to explain humans' place in the universe. You won't be able to tell this just from the first two sentences alone, but they're merely background context. We'll return to the first two sentences later to examine how we should know that they're not part of the author's reasoning.

The author's argument begins with the third sentence, which asserts that the truth of science is based on how well science helps us cope with the human condition. The more it helps us cope, the more truthful. The less it helps us cope, the less truthful. Here, the author gives us a premise defining how we measure the truthfulness of science because she's about to apply this definition.

Using the given measure of truthfulness in science, how truthful is science? The author believes it's not completely truthful. What's the support for this? The fact that science is to some degree responsible for the breakdown of society's key institutions. In the author's mind, science's role in the breakdown of these institutions implies that science isn't doing a perfect job at helping us cope with the human conditions. Thus, using the measure of truthfulness of science described earlier, the author concludes that science isn't completely truthful.

The summary above tries to give a substantive understanding of the argument to help you see why "science isn't completely truthful" is the author's conclusion. But there are also indicators here that are helpful for identifying the conclusion accurately.

• The word "so" tells us that the author's claim about the question of truth in science is offered to support the claim that science falls short of complete truth.
• The word "while" tells us that the part about science's successes is a concession point that isn't part of the author's premises or conclusion.
• The phrase "is amply demonstrated by" tells us that the final claim about breakdown of key institutions is designed to support the claim that science falls short of complete truth.

You might be wondering how we know that the first two sentences aren't relevant to the author's argument. First, notice that neither of the sentences provide support to each other or receive support from any other line. Why should we believe that humans have relied on myths to explain our place in the universe? The author doesn't provide support; she simply asserts that this is true. Why should we believe that the claims of science are similar to myths in that they try to explain our place in the universe? Again, there's no support offered for this claim. We simply must accept that it's true. So neither of the first two sentences contain the author's conclusion.

Next, observe that neither of the first two sentences provide support to anything else. Nothing about the author's reasoning would change if the first two sentences were removed. The author can still define the measure of truthfulness in science and apply that measure to reach the conclusion that science isn't completely truthful. The logic of the author's argument is focused solely on the truth of science; the similarity to myth is simply rhetorical flair the LSAT writers include to confuse us.

(By the way, in case you're confused by the word "since" at the beginning of the stimulus, that use of "since" doesn't introduce a premise. "Since" also has a temporal meaning, like in "I've been studying for the LSAT since last year." So don't think that the first sentence must play a logical role in the author's argument merely because of the word "since.")

(Some people might argue that the first two sentences provide support to the claim that the question of truth in science is the question of how well it helps us cope with the human condition. It's not worth getting into this view and why it's probably not accurate, because it doesn't change what we would identify as the main conclusion of the argument. Whether you view the first two sentences as just context or as premises, the main conclusion is still the claim that science isn't completely true.)

The author concludes that science falls short of complete truth.