I've seen this before (as most of the rest of the regulars here have as well). Just a couple of comments...
First, if the professor is teaching his class that his students "came from monkeys", he needs to be corrected. Nobody believes that to be the case. Ditto for "evolution never having been observed", which is blatantly and flagrantly false. Evolution has
Second, about the "not seeing God" versus "not seeing the professor's brain" thing -- it's amazing to me that this even needs to be pointed out, but brains can
be seen. Granted, most people never see their own brains because there's never a need, but there are x-rays, MRIs, or brain surgery when such need does arise. Conversely, God cannot be seen even in principle, a fact that even believers themselves acknowledge.
Regarding the heat/cold and light/dark thing, I was going to write a critique of that, but in researching, I found that Snopes, in their own analysis, has already torpedoed it...
The claim that cold "doesn't exist" because according to the laws of physics it's merely "the absence of heat" amounts to semantic game-playing. Heat is a noun, the name of a physical phenomenon, a form of energy. Cold is an adjective, a description. To say that something is cold, or that we feel cold, or even that we're going out in "the cold," is not to assert that cold "exists." It's simply a way of describing the relative temperature of things. (It's helpful to recognize that the proper antonym for cold isn't heat; it's hot.)
The same applies to light (in this context a noun denoting a form of energy), and dark (an adjective). It's true that when we say, "It's dark outside," the phenomenon we're actually describing is a relative absence of light, but that doesn't mean that by speaking of "the dark" we mistake it for a thing that "exists" in the same sense that light does. We're simply describing the degree of illumination we perceive.
So it's a philosophical parlor trick to posit heat and cold (or light and dark) as a pair of opposite entities only to "reveal" that the second term doesn't really refer to an entity at all, but merely the absence of the first.
To which I would also add that "hot and cold" and "light and dark" are terms for which we have reasonably objective measurements (that is, degrees of temperature and lumens). Even at that, though, they're still somewhat subjective terms. What I regard as a very comfortable and enjoyable outdoor temperature -- I generally prefer the upper fifites (Fahrenheit) or so -- may well be exceptionally cold for other people. The problem is greatly compounded when you attempt to extrapolate the analogy to "good and evil", where the mere existence of an objective standard, let alone what that standard actually is, is highly controversial.
In sum, as is always the case with apologetics... fail.