Episode Overview

Podcast: Making Sense with Sam Harris
Episode: #448 — The Philosophy of Good and Evil
Date: December 8, 2025
Guest: David Edmonds (Philosopher, Author, and Creator of the "Philosophy Bites" podcast)

In this episode, Sam Harris sits down with philosopher and author David Edmonds to discuss the evolution of moral philosophy, focusing particularly on effective altruism and the enduring power of philosophical thought experiments. The discussion weaves through the work and impact of influential philosophers like Peter Singer and Derek Parfit, examines key thought experiments (the Trolley Problem and the Shallow Pond), and interrogates the philosophical intuitions that shape our sense of good and evil.

Key Discussion Points & Insights

1. David Edmonds: Background & Motivation for the Book

• (01:54) Edmonds explains his background as both a BBC journalist and philosopher, now focusing solely on philosophy and his podcast "Philosophy Bites".
• He discusses his motivation for writing "Death in a Shallow Pond," intended as a biography of Peter Singer and a history of consequentialism, ultimately structured around Singer's famous "Shallow Pond" thought experiment.

2. Thought Experiments in Moral Philosophy

• Thought Experiments: For and Against
  [04:25]
  • Pro: Thought experiments strip away real-world noise to focus on core problems.
  • Con: Moral intuitions are built for real life, not "wacky" artificial scenarios. Skeptics argue results might not translate into practical reality.
  • Edmonds explains: "The real world is just full of Muzak and noise and complications. And so the thought experiment is designed to simplify and clarify."
• Sam Harris describes thought experiments as “conceptual and even emotional surgery” aimed at clarifying the moral terrain (06:43).

3. The Trolley Problem: A Moral Puzzle

• Classic Cases Described
  [07:28–09:54]
  • The original and variant forms (footbridge/pushing a man with a heavy rucksack) are recounted.
  • Edmonds: “Almost everybody thinks that in the first case, it is right to turn the train, and in the second case, it's wrong to push the fat man or the man with a heavy rucksack.” (09:14)
• Sam notes the “dissociation...is really extreme. It's something like 95% for and against in both cases. But the groups flip.” (09:54)

Memorable Quote:

“There’s this up close and personal, very affect driving image of actually touching the person and being the true proximate cause of his death.”
— Sam Harris, (10:19)

4. Consequentialism: Definitions and Defenses

• Consequentialism Defined
  [12:41]
  • Edmonds: "Consequentialism is the theory that what matters purely are the consequences."
• Trolleyology: The branch of philosophical inquiry around such scenarios.
• Discussing ingenious variations to tease apart intuition—such as the trapdoor version that removes the element of personal contact but preserves instrumental use of the person.

Memorable Quote:

“If you are a pure consequentialist, it looks like there's no difference between these two cases.”
— David Edmonds, (12:45)

• Sam’s Critique: Arguments against consequentialism often ignore broader consequences (e.g., trust in doctors or psychological harm in society) and focus too narrowly on simple body counts.
  [14:46]
  • "If in fact it is just fundamentally different experientially for a person to push someone to his death than to flip a switch, ... that's part of the set of consequences that we have to add to the balance." — Sam Harris, (14:46)
• Hospital/organ theft scenario: Used as a reductio against consequentialism.
• Sam argues these scenarios can be accommodated by a “fuller accounting of all the consequences.”

5. Means/Ends, The Doctrine of Double Effect, and Intention

• Edmonds references the doctrine of double effect:
  • Difference between intending harm (using someone as a means) vs. foreseeing harm (collateral damage).
  • Example: Targeting a munitions factory (knowing civilians will die) vs. targeting civilians directly.

Memorable Exchange:

David: "I think the key distinction is the distinction between intending and merely foreseeing. ... It's the difference between that and intentionally targeting those 100 civilians."
— (20:10)

Sam: “I'm not sure I totally buy that all turns on there being an important difference between acting in a way where it seems there's a 100% chance of killing a person, but still it being true to say that you don't intend to kill the person.”
— (19:49)

6. The Shallow Pond Thought Experiment and Everyday Morality

• Sam introduces the disconnect between philosophical intuitions and real-world behavior, using the example of speed limits in the U.S.
  [23:04]
  • Small policy changes (e.g., speed reducers) could save thousands, but society resists due to convenience and enjoyment.
  • Sam: “No one would want [speed limiters], no matter how many lives it would save, because it would be less fun to drive somehow.”
• Raises the issue: Are we all “moral monsters” for ignoring easily preventable large-scale harms?

Memorable Quote:

“Somehow the sense that there's even a moral problem here evaporates before I even can get to the end of the sentence.”
— Sam Harris, (23:54)

• Edmonds provides context: 40,000 US traffic deaths a year outstrip Vietnam War casualties, yet policy changes face resistance.
  (24:02)

Notable Quotes & Moments with Timestamps

• David Edmonds: “Thought experiments... are designed to simplify and clarify and try and get at the nub of a problem.” (05:52)
• Sam Harris: “It's a kind of conceptual and even emotional surgery that's being performed.” (06:43)
• David Edmonds: “[Trolleyology]—the study of these trolley cases is trollyology.” (13:01)
• Sam Harris: "...if in fact, I mean, just imagine being these two in one universe. You flip the switch, as 95% of people think you should, and your conscience is totally clear. In another universe, you flip the switch to the trapdoor and watch this man fall to his death and stop the train. And you can scarcely live with yourself because of the psychological toxicity of having had that experience. That's ...part of the consequences." (14:46)
• David Edmonds: "I think the key distinction is the distinction between intending and merely foreseeing." (20:10)
• Sam Harris: "Somehow the sense that there's even a moral problem here evaporates before I even can get to the end of the sentence." (23:54)

Important Timestamps

• 02:26 — Edmonds explains his philosophical background, podcast, and current projects
• 03:51 — Origin and intent of Edmonds’ new book; focus on Peter Singer and consequentialism
• 04:25–06:43 — The role and limits of thought experiments in philosophy
• 07:28–09:54 — Detailed walkthrough of the Trolley Problem and experimental outcomes
• 12:41–14:09 — Defining consequentialism, “trollyology”, and key case distinctions
• 14:46–16:57 — Sam’s argument: True consequentialism must account for all consequences, psychological and social as well as physical
• 17:30 — Philosophical counterfactuals and the manipulation of hypotheticals
• 20:10–20:24 — Intending harm vs. foreseeing collateral damage; discussion of double effect
• 23:04–24:02 — Real-world implications: Speed limits, preventable harm, and moral blindness

Concluding Notes

This episode offers a deep yet accessible exploration of foundational questions in moral philosophy, focusing on the gap between our moral reasoning in thought experiments and the real choices we make as individuals and societies. The conversation highlights the enduring value of philosophical analysis for clarifying our intuitions, the limitations of those intuitions, and the high personal and political stakes in deciding what we owe to others—far and near.

For more:

• Find David Edmonds' work and "Philosophy Bites" podcast online.
• Sam’s meditative and philosophical resources are available via the Waking Up app.

Summary covers content through [24:16], per transcript provided. All ads, intros, and outros omitted.