[O]ne of the great things about science is it forces us to refine our idea of what's common sense. It forces us to have our beliefs conform to the ev… - Lawrence M. Krauss

There's a loophole if you weigh galaxies and clusters because you're weighing the total amount of energy around galaxies. What if there's energy where galaxies aren't? What is where galaxies aren't? Nothing.

"[T]he declaration of a First Cause still leaves open the question, "Who created the creator?" After all, what is the difference between arguing in favor of an eternally existing creator versus an eternally existing universe without one?"

[I]n science we have to be particularly cautious about 'why' questions. When we ask, 'Why?' we usually mean 'How?' If we can answer the latter, that generally suffices for our purposes. For example, we might ask: 'Why is the Earth 93 million miles from the Sun?' but what we really probably mean is, 'How is the Earth 93 million miles from the Sun?' That is, we are interested in what physical processes led to the Earth ending up in its present position. 'Why' implicitly suggests purpose, and when we try to understand the solar system in scientific terms, we do not generally ascribe purpose to it.