Recent studies of spider phobia have indicated that fear of spiders is closely associated with the disease-avoidance response of disgust.
It is argued that the disgust-relevant status of the spider resulted from its association with disease and illness in European cultures.
The "Disgusting" Spider : The Role of Disease and illness in the Perpetuation of Fear of Spiders; Graham C. L. Davey ; The City University, London
The spider is a receptacle for emotions that come from the web.
Image caused by the presence or imminence of danger, because there is nothing to fear but birds, ornithophobia and fear itself.
Free spiders let their hair down, and meaningless sentences causes people to become sick from worry.