There are four stories in this book, so I guess it qualifies as an anthology. However, I usually consider anthologies to be at least 10 stories… maybe 8 (just to be generous).
Let me say this first: I recommend buying this book. Not every story is for everyone. Some of the stories spoke to me, while others did not. My co-author had some completely different opinions. So, maybe he’s right. Maybe I’m right. Maybe we’re both wrong. Decide for yourself.