Question: Is there any value in silence? Answer: Yes, without a doubt, yes.
Question: What value, exactly, does silence have? Answer: The value of silence, (positive, negative or null), is dependent on not only the cause and effect of the silence but on the observers perspective as well.
In the interest of brevity, the author assumes the reader agrees with the answer provided for the first question. Accepting silence has value I now address the second question, "What, exactly, is the value of silence?" My given answer states the value of silence is dependent on its cause, effect, the observers point of view and further that the value varies from good (positive) to bad (negative) including no effect (null, nil, or none). For example, consider the following situation:
Assume, I see you are in the path of an oncoming vehicle you don't. Also assume I will benefit from your demise and therefore remain silent. Finally assume my silence results in your being killed.
From your point of view the value of my silence would be less than none since the effect of my silence is your death, therefore the value of my silence to you is negative. From my point of view the value of my silence is greater than none since your death will benefit me, therefore the value of my silence to me is positive.
Observe that my presence is not necessary to produce the silence by which you remain un-informed of danger, are run over and die. My absence does nothing to change the events, your death; or, the benefit your demise has to me. Clearly, therefore, the cause is less important than the effect while it should be obvious perspective, no matter the cause or effect, ultimately defines the value of silence.