In his discussion of what it takes to make something profound, Ridley lays out four stipulations: depth, insight, significance, and value. However, in his explanation of these four, I think that he makes his definitions incredibly hazy - particularly for insight and significance - and thereby weakens his argument. In his discussion of insight, he says that, in order to be profound, the object in question must offer insight into what is going on in a specific example. But, he goes on, still under the heading of insight, to say that the theory, art, or view must offer insight into something important, rather than something that would be merely "a mildly interesting observation," as in the case of the enlarged '0' in the roulette wheel. Without this importance, the theory cannot be epistemically profound. He then goes on to say much the same thing in his discussion of significance though, again arguing that in order to be profound, the theory or view cannot merely describe anything, but something that is important to us. This importance he leaves very hazy, as far as I can tell, though he finds his own description satisfactory, and moves on to say that, to be profound, the idea must also have value - that is, it must have significance to us. It seems to me not only that his arguments, particularly for significance, are circular, but largely unnecessary and repetitive, which weakens the argument. I do not know why he includes the discussion of significance in his description of insight; he could merely say that, in the example of the roulette wheel, that the observation does indeed pass the insight test, but does not qualify as profound because it is not significant. That is, he can simply describe insight as a necessary, but not a sufficient condition. It also seems like he can eliminate the discussion of value, as it seems hardly different from his talk of significance to us. Including all these separate fields in order to fit our intuitions I think obfuscates the main points, which could be handled more concisely, and make for a stronger argument.
I also find his argument for significance strange independently, as it seems to circle around the idea of what significance is, without really settling much. He vacillates, wanting to secure some objective criteria for significance, but, unable to do so, seems to settle on a broad, almost universal subjectivism - that is, significance depends on its relation to all of us as humans. This seems to me to be a very hazy definition, especially in the way in which he circles around, trying to find solid ground on which to base his idea of significance.