Is there an official rule that the minimum damage can't be negative?

Question

A slightly humorous thought occurred to me (a recovering rules lawyer) after reading this question and answers.

"None of the answers actually specify that 0 is the minimum damage."

Logically it wouldn't make sense for an attack to apply negative damage or healing, except in specific cases like hitting a flame elemental with a fire attack. Ruling that you could do negative damage would lead to an exploit to avoid costs of healing. As such I highly doubt any DM would make such a ruling. I definitely wouldn't except for the most absurd and humorous of games were failure is the expected result not success.

Another possibility (as suggested by Secespitus) is that negative damage would reflect back on the attacker. This could be seen as punching a strongman so hard (or in just the wrong way) as to injure your own hand. This would also play well in a failure is the only option game, and if there is a rule suggesting that it would be an appropriate answer to this question as well.

Take the case of a person with less than 8 Strength, no levels in monk, and does not have a tavern brawler. Would they do -1(1 - 2) damage on unarmed strikes? If so what would the result of the negative damage be?

• "Healing" the target because such a puny hit actually raises their fighting spirits and makes them more capable of fighting
• Reflective Damage, the attacker actually takes 1 point of damage, representing injury to his hand or other damage

I am curious to know if there is an official rule stating that the minimum damage an attack can do is 0 or is there something in the damage calculation that I am missing that would otherwise prevent negative damage?

Answer 1

The rules in the SRD say: "With a penalty, it is possible to deal 0 damage, but never negative damage."

Answer 2

The SRD has a rule preventing negative damage. Some other sources do not specifically mention this case.

The rules in the SRD say:

"With a penalty, it is possible to deal 0 damage, but never negative damage."

^{SRD PDF (page 96)}

In the corresponding section in the PHB this sentence wasn't in the initial printings but was added sometime before the 4th printing.

^{PHB, Version 1.22, 017/PHB, fourth printing}

However since the SRD is to be seen as a free to use subset of the rules available in the official publications it can be assumed that the rule is meant to be in the official rules but was most likely excluded for formatting purposes.

Other sources of rules are also relatively silent on this matter, the closest Sage Advice states:

There is no damage minimum in the rules, so it is possible to deal 0 damage with an attack, a spell, or another effect.

^{SA Compendium Version 2.1, 2017}

Given the infrequency of negative damage actually occurring, and the SRD having a specific rule about it, it is safe to assume that negative damage just hasn't merited official response.

^{Thanks to Matt Vincent for finding the rule
Thanks to Josh Clark and KorvinStarmast for finding that the rule isn't in other location
Thanks to PaulZ for pointing out it is in some printings of the PHB}