This passage is an English translation of Surah Al-Munafiqun (63:4) from the Quran, which describes the traits of hypocrites (munafiquun).
The reference to "logs" (or "planks/timbers of wood propped up against a wall") is not a literal statement about tree logs reacting to sound vibration, but rather a literary metaphor used to describe human psychology and internal stress.
There are two primary ways to understand this passage: its linguistic/metaphorical context and the scientific/psychological explanation for why these "standing logs" act paranoid.
1. The Metaphor: Why "Standing Logs"?
In Arabic, the phrase is khushubun musannadah (propped-up timber).
- Hollow, rigid, and useless: Timber cut down and propped against a wall serves no active structural purpose. It is inanimate, lacks a soul or genuine foundation, and relies on external support to stay upright.
- Impressive shell, empty core: The verse contrasts their physical attractiveness and eloquent speech with their inner lack of substance. Outwardly they look strong like solid timber, but inwardly they are hollow and void of genuine conviction.
2. The Scientific & Psychological Explanation
When the text says "They think that every call/cry is intended against them," it describes a well-documented psychological phenomenon: Hypervigilance caused by the fear of exposure (Guilt-Induced Paranoia).
Psychology: Persecutory Guilt & Paranoia
- The Guilty Conscience: Individuals maintaining a deceptive double life experience chronic subconscious anxiety about being caught. Because their public persona contradicts their private motives, their brain interprets ambiguous external stimuli (a sudden noise, a raised voice, a call to gather) as an impending threat or exposure.
- Self-Referential Bias: This cognitive distortion leads individuals to believe that random events or general announcements are secretly about them or targeted at them.
Neuroscience: Chronic Stress & Acoustic Sensitivity
- Fight-or-Flight Activation: When someone lives under constant stress or fear of deceit being uncovered, the amygdala (the brain's threat-detection center) remains chronically overactive.
- Auditory Hypersensitivity: Under high stress or paranoia, the brain's sensory gating mechanisms weaken. Sudden auditory inputs—like a loud voice, a shout, or a call—trigger an exaggerated involuntary startle reflex, causing the person to misinterpret a normal voice or sound as an active attack.
Botanical/Acoustic Note on Real Trees
If considered from a literal plant biology perspective regarding whether actual wood/trees get "stressed" by sound waves or voices:
- Plant Mechanosensation: Plants and trees do respond to mechanical acoustic vibrations (such as specific sound frequencies or the buzzing of insects), which can alter gene expression or water transport.
- Log Inanimate State: Once a tree is cut into a "log" or "timber," it is dead plant tissue (xylem). It does not experience biological stress or auditory perception.
Thus, the text uses "standing logs" as a symbol of rigid, hollow human bodies who, despite their confident appearance, are paralyzed by psychological stress and paranoia whenever they hear a loud call.