A manual for writers of research papers, theses, and dissertations, Ninth edition - Kate L. Turabian 2018

Prefer arguments based on evidence to arguments based on warrants
Constructing your argument
Research and writing

Finally, it’s important to note that readers judge arguments based on warrants and arguments based on evidence differently.

✵ ▪ The first type of argument infers a claim from a reason and warrant. The claim in that kind of argument is believed to be certainly true.

✵ ▪ The second type supports a claim with reasons based on evidence. The claim in that kind of argument is considered to be probably true.

Contemporary readers generally trust the second kind more than the first. Compare these two examples:

We should do what we can to discourage teenagers from texting and driving,_claim because that behavior increases the risk of having an accident._{reason 1} Driving is difficult and texting a distraction,_{reason 2 supporting reason 1} and we know that when people are distracted while performing complex tasks, their performance suffers._{warrant linking reason 2 and reason 1}

We should do what we can to discourage teenagers from texting and driving,_claim because distracted driving is a leading cause of teenage deaths._reason According to the CDC, motor vehicle accidents are responsible for over a third of all fatalities among people aged 12—19, and texting while driving exponentially increases the likelihood that any driver will be involved in one. Moreover, . . . _evidence

If you are like most contemporary readers, you probably preferred the second of these arguments to the first. That’s because its warrant is not controversial (and therefore goes without saying) and its claim is supported by a reason based on solid evidence. That first argument seems plausible because an uncontroversial (and therefore unstated) warrant connects reason 1 to the claim, and an explicit warrant connects reason 2 to reason 1 (reason 1 is the claim reason 2 supports). In other words, reason 1 and reason 2 are good instances of that warrant’s general consequence and condition, respectively. Even so, as tight as that argument is, most readers still want some hard evidence.

In particular, you can rarely support a claim of fact with a warrant and reason alone. Generally, we can’t just reason our way to the facts; we have to discover them through research. Except in a few fields—some branches of mathematics, philosophy, theology—the way to demonstrate a claim of fact is to show with evidence that what you are claiming is, in fact, the case.

All arguments rely on warrants, but readers of research arguments are likely to mistrust arguments from principle alone. So whenever you can, rely not on elaborate lines of reasoning based on warrants but on hard evidence.