In this video, Jordan MacKenzie discusses a type of informal fallacy known as the argumentum ad populum fallacy, or the appeal to the people fallacy. This fallacy occurs when one attempts to establish the truth of a conclusion by appealing to the fact that the conclusion is widely believed to be true.
In this video, Kelley builds on the understanding of necessary and sufficient conditions laid out in her previous video on the topic (youtu.be/5LqNm9d2__I). In addition to providing further illustrative examples, Kelley addresses a new complexity: that our judgments of necessity and sufficiency very often rely on implicit background assumptions. Kelley also tackles the difficult question "What's so important about distinguishing necessary from sufficient conditions anyway?".
In part 3 of the series on conditionals, Justin picks up where part 2 (http://youtu.be/Xs6E-FEls1c) leaves off, introducing an alternative theory of conditionals: the strict conditional theory. According to the strict theory, conditionals express necessary connections between their antecedent and consequent. Justin shows how this theory avoids the problems facing the material conditional theory. However, the strict theory turns out to face a similar problem of its own!
Justin Khoo (M.I.T.) invites us to think about conditional sentences ("if P then Q"). Perhaps surprisingly, the question of what these sentences mean has vexed philosophers for thousands of years. In part 2 of the series on conditionals, Justin discusses some of the challenges facing the material conditional theory, picking up where part 1 (http://youtu.be/4Zxp2-_pLCE) left off.
In this video, Geoff Pynn (Northern Illinois University) follows up on his introduction to critical thinking by exploring how deductive arguments give us reason to believe their conclusions. Good deductive arguments guarantee their conclusions, and so must be valid (i.e., it must be impossible for the premises to be true while the conclusion is false) and have true premises. Philosophers call arguments like these "sound". You can see whether an argument is sound by trying to think of a counterexample to it, but to see whether its premises are true, you need to do some research.
What is human nature? Is human nature good or bad? Can human nature be good even if the world contains some notably bad people? Matthew Walker (Yale-NUS College) looks at the views of the early Confucian thinker Mengzi (Mencius).
In this video, Julianne Chung (Yale University) offers a brief introduction to ad hominem fallacies, or fallacies of personal attack. She surveys six different types (abusive ad hominem, circumstantial ad hominem, tu quoque, guilt by association, genetic fallacy, and ad feminam), offering examples of each along the way. For a more detailed discussion of ad hominem fallacies, please see the video on ad hominem fallacies by Paul Henne (Duke University).
"I think, therefore I am" - almost everyone has heard of René Descartes' famous cogito argument. But what is this argument about? What does it show, and why are so many philosophers excited about it - even today, more than 350 years after Descartes first presented this argument?
In this video, Julianne Chung (Yale University) explains the philosophical concepts of truth and validity before going on to illustrate how truth and falsity, as well as validity and invalidity, can appear in various combinations in an argument. She then introduces the concept of a sound argument (i.e., a valid argument whose premises are all true) and presents one reason to think that valid arguments with false premises are also of interest. For more detailed discussions of validity and soundness, please be sure to have a look at the videos on these topics by Paul Henne (Duke University) and Aaron Ancell (Duke University), respectively.
How do we know stuff about matters of fact that we have yet to observe? For example, how do I know that the sun will rise tomorrow? A natural answer is that we have this knowledge through induction: I know the sun will rise tomorrow, because it has risen every day in the past. Now, the philosopher David Hume recognized that this inductive reasoning assumes that the future will resemble the past. Why though think that this assumption is true? How do we know that the future will resemble the past? This question is the starting point for Hume's skeptical argument against induction (and his skeptical solution), which Daniel Greco lays out in detail in this video.
According to the philosopher David Hume (1711-1776), absolutely everything we know falls into one of two categories: either it is a relation of ideas (e.g., 2 + 2 =4) or it is a matter of fact (e.g., the sky is blue). Daniel Greco walks us through this famous Humean distinction in preparation for examining Hume's even more famous skeptical argument against induction.
In this video, Aaron Ancell (Duke University) discusses the philosophical concept of soundness. After reviewing validity, he defines soundness: an argument is sound when it is valid and has all true premises. He reviews a few examples of sound and unsound arguments, and he encourages you to develop sound arguments on your own.
In this video, Paul Henne (Duke University) discusses the philosophical concept of validity. After reviewing the structure of an argument, he defines validity: an argument is valid if and only if its premises guarantee the conclusion. He reviews a few examples of validity and invalidity, and he leaves you with one example to figure out on your own.
Scott Edgar returns to Kant's argument from Geometry, this time examining two famous objections to it: the famous "neglected alternative" objection and a powerful objection from 20th century physics. After considering possible responses on Kant's behalf, Scott ends with a bang, introducing Kant's famous claim that we know things only as they appear to us, not as they are in themselves.
What is space? Kant's answer is a head-scratcher: space is merely a form of intuition. Scott Edgar explains this rather perplexing answer in accessible, every-day language. He also lays out Kant's most famous argument for this view of space (the "Argument from Geometry"). Never before has it been so easy to get a handle on Kant's views on space!
Scott Edgar (Saint Mary's University) discusses Kant's views on knowledge of metaphysics. Scott introduces us to distinctions between "a priori" and "empirical" knowledge and also the distinction between "analytic" and "synthetic" claims.