Times have certainly changed. This book was written back in the days when spiking your roommate's orange juice with LSD could be considered just a practical joke, instead of what it is today: a criminal offense. On the other hand, in those days publicly smoking pot could net you some serious jail time, while today the green stuff is legal in various states. Drugs of all kinds were perceived by many as new, exciting and fun, instead of being the daily bread of their grandchildren who, in the new millenium, think nothing of putting their elementary kids on antidepressants, or taking them themselves for years on end.
A companion piece to The Unicorn Girl, I found Anderson's volume of the Greenwich Village Trilogy better written and more engaging than Kurland's attempt. Huge blue lobsters from an alien galaxy are bent on taking over the Earth. It's up to Anderson, Kurland, and their flower-powered friends to save the planet, the day and the New York City water supply. Unfortunately, I have yet to unearth a copy of The Probability Pad, not even online, so I'll never know how it all turned out.
(By the way—ever notice how all extraterrestrials refer to our planet as Terra, in every sci-fi movie, book or comic you've ever seen? Do you suppose other life forms speak Latin?)